Common use of Trust Clause in Contracts

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 2-CB-3 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 Class 2-CB-3 Certificate Interest Rate: 5.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 Principal Balance as of the Cut-Off Date: $149,937,994.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 2-CB-3 CB-6 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 41,289,416.00 Class 2-CB-3 CB-6 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 CB-6 Principal Balance as of the Cut-Off Date: $149,937,994.00 41,289,416.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 1-A-7 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 Portion of the Class 21-CB-3 A-7 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,000,000.00 Class 21-CB-3 A-7 Certificate Interest Rate: 5.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August September 25, 2035 Class 21-CB-3 A-7 Principal Balance as of the Cut-Off Date: $149,937,994.00 1,000,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 21-CB-3 A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 59,304,107.00 Class 21-CB-3 A-4 Certificate Interest Rate: 5.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August September 25, 2035 Class 21-CB-3 A-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 59,304,107.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 2-CB-2 Certificates will provide credit support to other Classes of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 Portion of the Class 2-CB-3 CB-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 4,195,000.00 Class 2-CB-3 CB-2 Certificate Interest Rate: 5.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 CB-2 Principal Balance as of the Cut-Off Date: $149,937,994.00 4,195,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 2-CB-3 CB-7 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 3,753,584.00 Class 2-CB-3 CB-7 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 CB-7 Principal Balance as of the Cut-Off Date: $149,937,994.00 3,753,584.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 2-CB-3 CB-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 24,424,200.00 Class 2-CB-3 CB-1 Certificate Interest Rate: 5.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 CB-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 24,424,200.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Interest is not payable with respect to this Certificate. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 2C-CB-3 P Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,897,569.00 Class 2C-CB-3 P Certificate Interest Rate: 5.5000.00% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August September 25, 2035 Class 2C-CB-3 P Principal Balance as of the Cut-Off Date: $149,937,994.00 1,897,569.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 21-CB-3 A-8 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 4,215,000.00 Class 21-CB-3 A-8 Certificate Interest Rate: 5.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August September 25, 2035 Class 21-CB-3 A-8 Principal Balance as of the Cut-Off Date: $149,937,994.00 4,215,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 24-CB-3 CB Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 29,539,800.00 Class 24-CB-3 CB Certificate Interest Rate: 5.5007.000% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 24-CB-3 CB Principal Balance as of the Cut-Off Date: $149,937,994.00 29,539,800.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended, together with certain rights specified in the Pooling Agreement. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 21-CB-3 A-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 50,000,000.00 Class 21-CB-3 A-2 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August September 25, 2035 Class 21-CB-3 A-2 Principal Balance as of the Cut-Off Date: $149,937,994.00 50,000,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 23-CB-3 CB Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 37,805,200.00 Class 23-CB-3 CB Certificate Interest Rate: 5.5006.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 23-CB-3 CB Principal Balance as of the Cut-Off Date: $149,937,994.00 37,805,200.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 2-CB-3 CB-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 31,569,066.00 Class 2-CB-3 CB-4 Certificate Interest Rate: 5.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 CB-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 31,569,066.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 2-CB-3 CB-5 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 31,022,740.00 Class 2-CB-3 CB-5 Certificate Interest Rate: 5.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 CB-5 Principal Balance as of the Cut-Off Date: $149,937,994.00 31,022,740.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 21-CB-3 A-5 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 16,001,326.00 Class 21-CB-3 A-5 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August September 25, 2035 Class 21-CB-3 A-5 Principal Balance as of the Cut-Off Date: $149,937,994.00 16,001,326.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 21-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 13,552,800.00 Class 21-CB-3 A-1 Certificate Interest Rate: 5.500% Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August September 25, 2035 Class 21-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 13,552,800.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 Portion of the Class 2C-CB-3 Principal Balance X Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 14,369,296.00 Class 2C-CB-3 X Certificate Interest Rate: 5.500% %, applied to the Class C-X Notional Amount Cut-Off Date: August 1, 2005 First Distribution Date: September 26, 2005 Last Scheduled Distribution Date: August September 25, 2035 Class 2C-CB-3 X Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class C-X Notional Amount as of the Cut-Off Date: $14,369,296.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26March 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 2 Portion of the Class 23-CB-3 A Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 26,468,300.00 Class 23-CB-3 A Certificate Interest Rate: 5.500% Cut-Off Date: August March 1, 2005 First Distribution Date: September 26April 25, 2005 Last Scheduled Distribution Date: August April 25, 2035 2020 Class 23-CB-3 A Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 26,468,300.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 1 Portion of the Class 21-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 149,000,000.00 Class 21-CB-3 A-1 Certificate Interest Rate: 5.500% Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 Class 21-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 149,000,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 A-7 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 72,000,000.00 Class 2-CB-3 A-7 Certificate Interest Rate: 5.5005.750% Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 A-7 Principal Balance as of the Cut-Off Date: $149,937,994.00 72,000,000.00 Registered Owner Exhibit A CUSIP 93934F JC7 Class A-8 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26January 30, 20052006. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 20052006-7 1 Portion of the Class 25-CB-3 CB-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 184,322,400.00 Class 25-CB-3 CB-4 Certificate Interest Rate: 5.5005.750% Cut-Off Date: August January 1, 2005 2006 First Distribution Date: September 26February 27, 2005 2006 Last Scheduled Distribution Date: August February 25, 2035 2036 Class 25-CB-3 CB-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 184,322,400.00 Registered Owner Exhibit A CUSIP 93934F LD 2 Class 5-CB-5 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26July 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 6 Portion of the Class 23-CB-3 CB Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 96,253,000.00 Class 23-CB-3 CB Certificate Interest Rate: 5.500% Cut-Off Date: August July 1, 2005 First Distribution Date: September 26August 25, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 23-CB-3 CB Principal Balance as of the Cut-Off Date: $149,937,994.00 96,253,000.00 Cede & Co. Registered Owner WASHINGTON MUTUAL MORTGAGE PASS-THROUGH CERTIFICATE Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26January 30, 20052006. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 20052006-7 1 Portion of the Class 25-CB-3 CB-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 24,308,000.00 Class 25-CB-3 CB-1 Certificate Interest Rate: 5.5005.750% Cut-Off Date: August January 1, 2005 2006 First Distribution Date: September 26February 27, 2005 2006 Last Scheduled Distribution Date: August February 25, 2035 2036 Class 25-CB-3 CB-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 24,308,000.00 Registered Owner Exhibit A CUSIP 93934F LA 8 Class 5-CB-2 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT The Class 1-A-2 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. Series 2005-7 1 Portion of the Class 2Clas 1-CB-3 A-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 5,960,000.00 Class 21-CB-3 A-2 Certificate Interest Rate: 5.500% Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 Class 21-CB-3 A-2 Principal Balance as of the Cut-Off Date: $149,937,994.00 5,960,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 25-CB-3 A-5 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 36,000,000.00 Class 25-CB-3 A-5 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 25-CB-3 A-5 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 36,000,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26March 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 2 Portion of the Class 2-CB-3 A-5 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 2,225,000.00 Class 2-CB-3 A-5 Certificate Interest Rate: 5.500% Cut-Off Date: August March 1, 2005 First Distribution Date: September 26April 25, 2005 Last Scheduled Distribution Date: August April 25, 2035 Class 2-CB-3 A-5 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 2,225,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 Principal Balance A-4 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 53,263,000.00 Class 2-CB-3 A-4 Certificate Interest Rate: 5.500% Variable, applied to the Class A-4 Notional Amount Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 A-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class A-4 Notional Amount as of the Cut-Off Date: $53,263,000.00 Exhibit A CUSIP 93934F HZ8 Class A-5 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26November 29, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 10 Portion of the Class 23-CB-3 CB-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 109,200,200.00 Class 23-CB-3 CB-1 Certificate Interest Rate: 5.5006.000% Cut-Off Date: August November 1, 2005 First Distribution Date: September 26December 27, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 23-CB-3 CB-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 109,200,200.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 CB-13 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 107,250,000.00 Class 2-CB-3 CB-13 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2-CB-3 CB-13 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 107,250,000.00 Registered Owner Exhibit A CUSIP 939336 6J 7 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 4-A-2 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 4 Portion of the Class 24-CB-3 A-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,484,000.00 Class 24-CB-3 A-2 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 2020 Class 24-CB-3 A-2 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 1,484,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26March 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 2 Portion of the Class 21-CB-3 A-6 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 10,700,000.00 Class 21-CB-3 A-6 Certificate Interest Rate: 5.500% Cut-Off Date: August March 1, 2005 First Distribution Date: September 26April 25, 2005 Last Scheduled Distribution Date: August April 25, 2035 Class 21-CB-3 A-6 Principal Balance as of the Cut-Off Date: $149,937,994.00 10,700,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 1 Portion of the Class 25-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 58,645,000.00 Class 25-CB-3 A-1 Certificate Interest Rate: 5.5006.000% Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 Class 25-CB-3 A-1 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 58,645,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 25-CB-3 A-6 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 36,000,000.00 Class 25-CB-3 A-6 Certificate Interest Rate: 5.500% Variable, applied to the Class 5-A-6 Notional Amount Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 25-CB-3 A-6 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class 5-A-6 Notional Amount as of the Cut-Off Date: $36,000,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 5-A-10 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 4 Portion of the Class 25-CB-3 A-10 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 445,000.00 Class 25-CB-3 A-10 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 25-CB-3 A-10 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 445,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class A-9 Certificates will provide credit support to certain Classes of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 A-9 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 7,330,000.00 Class 2-CB-3 A-9 Certificate Interest Rate: 5.5005.750% Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 A-9 Principal Balance as of the Cut-Off Date: $149,937,994.00 7,330,000.00 Registered Owner Exhibit A CUSIP 93934F JE3 Class X Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26November 29, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 10 Portion of the Class 25-CB-3 A Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 30,190,000.00 Class 25-CB-3 A Certificate Interest Rate: 5.500% Cut-Off Date: August November 1, 2005 First Distribution Date: September 26December 27, 2005 Last Scheduled Distribution Date: August November 25, 2035 2020 Class 25-CB-3 A Principal Balance as of the Cut-Off Date: $149,937,994.00 30,190,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 Principal Balance CB-4 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 154,500,000.00 Class 2-CB-3 CB-4 Certificate Interest Rate: 5.500% Variable, applied to the Class CB-4 Notional Amount Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2-CB-3 CB-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class CB-4 Notional Amount as of the Cut-Off Date: $154,500,000.00 Registered Owner Exhibit A CUSIP 939336 5Z 2 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 5-A-2 Certificates will provide credit support to other Classes of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 9 Portion of the Class 25-CB-3 A-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,000,000.00 Class 25-CB-3 A-2 Certificate Interest Rate: 5.500% Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 25-CB-3 A-2 Principal Balance as of the Cut-Off Date: $149,937,994.00 1,000,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26July 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 6 Portion of the Class 2-CB-3 A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 95,000,000.00 Class 2-CB-3 A-4 Certificate Interest Rate: 5.500% Cut-Off Date: August July 1, 2005 First Distribution Date: September 26August 25, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 A-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 95,000,000.00 Cede & Co. Registered Owner WASHINGTON MUTUAL MORTGAGE PASS-THROUGH CERTIFICATE Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August April 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT The Class 1-CB-2 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. Series 2005-7 3 Portion of the Class 21-CB-3 CB-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 2,049,000.00 Class 21-CB-3 CB-2 Certificate Interest Rate: 5.500% Cut-Off Date: August April 1, 2005 First Distribution Date: September 26May 25, 2005 Last Scheduled Distribution Date: August May 25, 2035 Class 21-CB-3 CB-2 Principal Balance as of the Cut-Off Date: $149,937,994.00 2,049,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 25-CB-3 A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 8,555,000.00 Class 25-CB-3 A-4 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 25-CB-3 A-4 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 8,555,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 5-A-2 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 1 Portion of the Class 25-CB-3 A-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,760,500.00 Class 25-CB-3 A-2 Certificate Interest Rate: 5.5006.000% Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 Class 25-CB-3 A-2 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 1,760,500.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 2-A-7 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 9 Portion of the Class 2-CB-3 A-7 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,000,000.00 Class 2-CB-3 A-7 Certificate Interest Rate: 5.500% Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 2-CB-3 A-7 Principal Balance as of the Cut-Off Date: $149,937,994.00 1,000,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 A-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 123,295,000.00 Class 2-CB-3 A-2 Certificate Interest Rate: 5.5005.750% Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 A-2 Principal Balance as of the Cut-Off Date: $149,937,994.00 123,295,000.00 Registered Owner Exhibit A CUSIP 93934F HX3 Class A-3 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 Principal Balance A-6 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 30,000,000.00 Class 2-CB-3 A-6 Certificate Interest Rate: 5.500% Variable, applied to the Class A-6 Notional Amount Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 A-6 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class A-6 Notional Amount as of the Cut-Off Date: $30,000,000.00 Exhibit A CUSIP 93934F JB9 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 1 Portion of the Class 24-CB-3 A Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 25,283,300.00 Class 24-CB-3 A Certificate Interest Rate: 5.500% Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 2020 Class 24-CB-3 A Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 25,283,300.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 7-A-4 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 1 Portion of the Class 27-CB-3 A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 226,200.00 Class 27-CB-3 A-4 Certificate Interest Rate: 5.500% Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 Class 27-CB-3 A-4 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 226,200.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 25-CB-3 A-7 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 108,199,000.00 Class 25-CB-3 A-7 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 25-CB-3 A-7 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 108,199,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26March 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 2-A-4 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 2 Portion of the Class 2-CB-3 A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 2,650,000.00 Class 2-CB-3 A-4 Certificate Interest Rate: 5.500% Cut-Off Date: August March 1, 2005 First Distribution Date: September 26April 25, 2005 Last Scheduled Distribution Date: August April 25, 2035 Class 2-CB-3 A-4 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 2,650,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 6-A-2 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 1 Portion of the Class 26-CB-3 A-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 530,400.00 Class 26-CB-3 A-2 Certificate Interest Rate: 5.5006.500% Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 Class 26-CB-3 A-2 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 530,400.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 9 Portion of the Class 25-CB-3 A-9 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 4,937,000.00 Class 25-CB-3 A-9 Certificate Interest Rate: 5.500% Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 25-CB-3 A-9 Principal Balance as of the Cut-Off Date: $149,937,994.00 4,937,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 A-3 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 53,263,000.00 Class 2-CB-3 A-3 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 A-3 Principal Balance as of the Cut-Off Date: $149,937,994.00 53,263,000.00 Registered Owner Exhibit A CUSIP 93934F HY1 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August April 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 3 Portion of the Class 2-CB-3 A-5 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 2,614,000.00 Class 2-CB-3 A-5 Certificate Interest Rate: 5.500% Cut-Off Date: August April 1, 2005 First Distribution Date: September 26May 25, 2005 Last Scheduled Distribution Date: August May 25, 2035 Class 2-CB-3 A-5 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 2,614,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 9 Portion of the Class 25-CB-3 A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 3,637,332.00 Class 25-CB-3 A-4 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 25-CB-3 A-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 3,637,332.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 24-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 28,498,000.00 Class 24-CB-3 A-1 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 2020 Class 24-CB-3 A-1 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 28,498,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26July 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 6 Portion of the Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 44,055,000.00 Class 2-CB-3 A-1 Certificate Interest Rate: 5.500% Cut-Off Date: August July 1, 2005 First Distribution Date: September 26August 25, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 44,055,000.00 Cede & Co. Registered Owner WASHINGTON MUTUAL MORTGAGE PASS-THROUGH CERTIFICATE Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 P Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,752,850.00 Class 2-CB-3 P Certificate Interest Rate: 5.5000.00% Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 P Principal Balance as of the Cut-Off Date: $149,937,994.00 1,752,850.00 Exhibit A CUSIP 93934F JG8 Class B-1 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26March 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 2 Portion of the Class 21-CB-3 A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 281,002,000.00 Class 21-CB-3 A-4 Certificate Interest Rate: 5.500% Variable, applied to the Class 1-A-4 Notional Amount Cut-Off Date: August March 1, 2005 First Distribution Date: September 26April 25, 2005 Last Scheduled Distribution Date: August April 25, 2035 Class 21-CB-3 A-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class 1-A-4 Notional Amount as of the Cut-Off Date: $281,002,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26November 29, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 10 Portion of the Class 21-CB-3 CB Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 62,532,200.00 Class 21-CB-3 CB Certificate Interest Rate: 5.5006.500% Cut-Off Date: August November 1, 2005 First Distribution Date: September 26December 27, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 21-CB-3 CB Principal Balance as of the Cut-Off Date: $149,937,994.00 62,532,200.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August April 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 3 Portion of the Class 21-CB-3 Principal Balance CB-4 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 356,447,000.00 Class 21-CB-3 CB-4 Certificate Interest Rate: 5.500% Variable, applied to the Class 1-CB-4 Notional Amount Cut-Off Date: August April 1, 2005 First Distribution Date: September 26May 25, 2005 Last Scheduled Distribution Date: August May 25, 2035 Class 21-CB-3 CB-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class 1-CB-4 Notional Amount as of the Cut-Off Date: $356,447,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 CB-6 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 500,000.00 Class 2-CB-3 CB-6 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2-CB-3 CB-6 Principal Balance as of the Cut-Off Date: $149,937,994.00 500,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26March 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 1-A-5 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 2 Portion of the Class 21-CB-3 A-5 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 14,790,000.00 Class 21-CB-3 A-5 Certificate Interest Rate: 5.500% Cut-Off Date: August March 1, 2005 First Distribution Date: September 26April 25, 2005 Last Scheduled Distribution Date: August April 25, 2035 Class 21-CB-3 A-5 Principal Balance as of the Cut-Off Date: $149,937,994.00 14,790,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 25,288,000.00 Class 2-CB-3 A-1 Certificate Interest Rate: 5.5005.750% Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 25,288,000.00 Registered Owner Exhibit A CUSIP 93934F HW5 Class A-2 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26July 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 6 Portion of the Class 2-CB-3 A-3 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 4,252,334.00 Class 2-CB-3 A-3 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August July 1, 2005 First Distribution Date: September 26August 25, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 A-3 Principal Balance as of the Cut-Off Date: $149,937,994.00 4,252,334.00 Cede & Co. Registered Owner WASHINGTON MUTUAL MORTGAGE PASS-THROUGH CERTIFICATE Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 9 Portion of the Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 22,300,000.00 Class 2-CB-3 A-1 Certificate Interest Rate: 5.500% Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 22,300,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 CB Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 28,570,000.00 Class 2-CB-3 CB Certificate Interest Rate: 5.5005.000% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 2020 Class 2-CB-3 CB Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 28,570,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August April 26, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 3 Portion of the Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 8,815,000.00 Class 2-CB-3 A-1 Certificate Interest Rate: 5.500% Cut-Off Date: August April 1, 2005 First Distribution Date: September 26May 25, 2005 Last Scheduled Distribution Date: August May 25, 2035 Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 8,815,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 Principal Balance CB-16 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 53,545.00 Class 2-CB-3 CB-16 Certificate Interest Rate: 5.5005.50% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2-CB-3 CB-16 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class CB-16 Notional Amount as of the Cut-Off Date: $53,545.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 Principal Balance CB-14 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 107,250,000.00 Class 2-CB-3 CB-14 Certificate Interest Rate: 5.500% Variable, applied to the Class CB-14 Notional Amount Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2-CB-3 CB-14 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class CB-14 Notional Amount as of the Cut-Off Date: $107,250,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 1 Portion of the Class 21-CB-3 A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 13,935,000.00 Class 21-CB-3 A-4 Certificate Interest Rate: 5.500% Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 Class 21-CB-3 A-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 13,935,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26July 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 2-A-10 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 6 Portion of the Class 2-CB-3 A-10 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 2,124,000.00 Class 2-CB-3 A-10 Certificate Interest Rate: 5.500% Cut-Off Date: August July 1, 2005 First Distribution Date: September 26August 25, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2-CB-3 A-10 Principal Balance as of the Cut-Off Date: $149,937,994.00 2,124,000.00 Cede & Co. Registered Owner WASHINGTON MUTUAL MORTGAGE PASS-THROUGH CERTIFICATE Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26November 29, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 10 Portion of the Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 26,790,200.00 Class 2-CB-3 A-1 Certificate Interest Rate: 5.5005.750% Cut-Off Date: August November 1, 2005 First Distribution Date: September 26December 27, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 2-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 26,790,200.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26January 30, 20052006. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 20052006-7 1 Portion of the Class 24-CB-3 CB Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 115,632,000.00 Class 24-CB-3 CB Certificate Interest Rate: 5.5006.500% Cut-Off Date: August January 1, 2005 2006 First Distribution Date: September 26February 27, 2005 2006 Last Scheduled Distribution Date: August February 25, 2035 2036 Class 24-CB-3 CB Principal Balance as of the Cut-Off Date: $149,937,994.00 115,632,000.00 Registered Owner Exhibit A CUSIP 93934F KZ 4 Class 5-CB-1 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26January 30, 20052006. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 20052006-7 1 Portion of the Class 25-CB-3 CB-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 26,945,000.00 Class 25-CB-3 CB-2 Certificate Interest Rate: 5.5005.750% Cut-Off Date: August January 1, 2005 2006 First Distribution Date: September 26February 27, 2005 2006 Last Scheduled Distribution Date: August February 25, 2035 2036 Class 25-CB-3 CB-2 Principal Balance as of the Cut-Off Date: $149,937,994.00 26,945,000.00 Registered Owner Exhibit A CUSIP 93934F LB 6 Class 5-CB-3 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26January 29, 20052007. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 2-A-2 Certificates will provide credit support to certain Classes of Certificates, as described in the Pooling Agreement. WMALT Series 20052007-7 1 Portion of the Class 2-CB-3 A-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,474,000.00 Class 2-CB-3 A-2 Certificate Interest Rate: 5.5006.000% Cut-Off Date: August January 1, 2005 2007 First Distribution Date: September February 26, 2005 2007 Last Scheduled Distribution Date: August January 25, 2035 2022 Class 2-CB-3 A-2 Principal Balance as of the Cut-Off Date: $149,937,994.00 1,474,000.00 Exhibit A CUSIP ▇▇▇▇▇▇▇▇▇ Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another trust that owns a pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed byby This Certificate is issued by Washington Mutual Mortgage Pass-Through Certificates WMALT Series 2007-1 Trust. This Certificate represents ownership of one or more “regular interests” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is January 29, 2007. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. This Certificate is a Subsequent Exchangeable Certificate, as described in the Pooling Agreement. WMALT Series 2007-1 Portion of the Class 2-A-3 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $0.00 Class 2-A-3 Certificate Interest Rate: 5.500% Cut-Off Date: January 1, 2007 First Distribution Date: February 26, 2007 Last Scheduled Distribution Date: January 25, 2022 Class 2-A-3 Principal Balance as of the Cut-Off Date: $0.00 Maximum Initial Class 2-A-3 Principal Balance: $30,225,000.00 Exhibit A CUSIP ▇▇▇▇▇▇▇▇▇ Evidencing a beneficial interest in a trust that owns a pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by This Certificate is issued by Washington Mutual Mortgage Pass-Through Certificates WMALT Series 2007-1 Trust. This Certificate represents ownership of one or more “regular interests” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is January 29, 2007. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. This Certificate is a Subsequent Exchangeable Certificate, as described in the Pooling Agreement. WMALT Series 2007-1 Portion of the Class 2-A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $0.00 Class 2-A-4 Certificate Interest Rate: 5.750% Cut-Off Date: January 1, 2007 First Distribution Date: February 26, 2007 Last Scheduled Distribution Date: January 25, 2022 Class 2-A-4 Principal Balance as of the Cut-Off Date: $0.00 Maximum Initial Class 2-A-4 Principal Balance: $30,225,000.00 Exhibit A CUSIP ▇▇▇▇▇▇▇▇▇ Evidencing a beneficial interest in a trust that owns a pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by This Certificate is issued by Washington Mutual Mortgage Pass-Through Certificates WMALT Series 2007-1 Trust. This Certificate represents ownership of one or more “regular interests” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is January 29, 2007. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. This Certificate is a Subsequent Exchangeable Certificate, as described in the Pooling Agreement. WMALT Series 2007-1 Portion of the Class 2-A-5 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $0.00

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 9 Portion of the Class 24-CB-3 A-4 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 12,231,900.00 Class 24-CB-3 A-4 Certificate Interest Rate: 5.500% Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 24-CB-3 A-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 12,231,900.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 P Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,752,850.00 Class 2-CB-3 P Certificate Interest Rate: 5.5000.00% Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 P Principal Balance as of the Cut-Off Date: $149,937,994.00 1,752,850.00 Exhibit A CUSIP 93934F JG8 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26November 29, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 10 Portion of the Class 2-CB-3 Principal Balance A-4 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 73,950,000.00 Class 2-CB-3 A-4 Certificate Interest Rate: 5.500% Variable, applied to the Class 2-A-4 Notional Amount Cut-Off Date: August November 1, 2005 First Distribution Date: September 26December 27, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 2-CB-3 A-4 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class 2-A-4 Notional Amount as of the Cut-Off Date: $73,950,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 1 Portion of the Class 23-CB-3 A Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 21,221,500.00 Class 23-CB-3 A Certificate Interest Rate: 5.5005.000% Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 2020 Class 23-CB-3 A Principal Balance as of the Cut-Off Date: $149,937,994.00 21,221,500.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2C-CB-3 Principal Balance X Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 32,170,450.00 Class 2C-CB-3 X Certificate Interest Rate: 5.500% applied to the Class C-X Notional Amount Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2C-CB-3 X Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class C-X Notional Amount as of the Cut-Off Date: $32,170,450.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26January 29, 20052007. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 20052007-7 1 Portion of the Class 21-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 9,501,300.00 Class 21-CB-3 A-1 Certificate Interest Rate: 5.5006.000% Cut-Off Date: August January 1, 2005 2007 First Distribution Date: September February 26, 2005 2007 Last Scheduled Distribution Date: August February 25, 2035 2037 Class 21-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 9,501,300.00 Exhibit A CUSIP ▇▇▇▇▇▇▇▇▇ Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another trust that owns a pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 A-5 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 30,000,000.00 Class 2-CB-3 A-5 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 A-5 Principal Balance as of the Cut-Off Date: $149,937,994.00 30,000,000.00 Exhibit A CUSIP 93934F JA1 Class A-6 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 5-A-9 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 4 Portion of the Class 25-CB-3 A-9 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 960,000.00 Class 25-CB-3 A-9 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 25-CB-3 A-9 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 960,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26March 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 2 Portion of the Class 21-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 31,122,000.00 Class 21-CB-3 A-1 Certificate Interest Rate: 5.500% Cut-Off Date: August March 1, 2005 First Distribution Date: September 26April 25, 2005 Last Scheduled Distribution Date: August April 25, 2035 Class 21-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 31,122,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26July 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 6 Portion of the Class 2C-CB-3 Principal Balance X Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 15,921,449.00 Class 2C-CB-3 X Certificate Interest Rate: 5.500% %, applied to the Class C-X Notional Amount Cut-Off Date: August July 1, 2005 First Distribution Date: September 26August 25, 2005 Last Scheduled Distribution Date: August 25, 2035 Class 2C-CB-3 X Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class C-X Notional Amount as of the Cut-Off Date: $15,921,449.00 Cede & Co. Registered Owner WASHINGTON MUTUAL MORTGAGE PASS-THROUGH CERTIFICATE Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26January 30, 20052006. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 5-CB-6 Certificates will provide credit support to certain Classes of Certificates, as described in the Pooling Agreement. WMALT Series 20052006-7 1 Portion of the Class 25-CB-3 CB-6 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,726,000.00 Class 25-CB-3 CB-6 Certificate Interest Rate: 5.5005.750% Cut-Off Date: August January 1, 2005 2006 First Distribution Date: September 26February 27, 2005 2006 Last Scheduled Distribution Date: August February 25, 2035 2036 Class 25-CB-3 CB-6 Principal Balance as of the Cut-Off Date: $149,937,994.00 1,726,000.00 Registered Owner Exhibit A CUSIP 93934F LF 7 Class C-X Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 1 Portion of the Class 2D-CB-3 Principal Balance X Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,414,828.00 Class 2D-CB-3 X Certificate Interest Rate: 5.500% applied to the Class D-X Notional Amount Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 2020 Class 2D-CB-3 X Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class D-X Notional Amount as of the Cut-Off Date: $1,414,828.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class CB-12 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 CB-12 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,698,000.00 Class 2-CB-3 CB-12 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2-CB-3 CB-12 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 1,698,000.00 Registered Owner Exhibit A CUSIP 939336 6H 1 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 9 Portion of the Class 2-CB-3 Principal Balance A-6 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 24,612,300.00 Class 2-CB-3 A-6 Certificate Interest Rate: 5.500% Variable, applied to the Class 2-A-6 Notional Amount Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 2-CB-3 A-6 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class 2-A-6 Notional Amount as of the Cut-Off Date: $24,612,300.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26February 25, 2005. Interest is not payable with respect to this Certificate. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 1 Portion of the Class 23-CB-3 P Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 Class 23-CB-3 P Certificate Interest Rate: 5.5000.00% $224,290.00 Cut-Off Date: August February 1, 2005 First Distribution Date: September 26March 25, 2005 Last Scheduled Distribution Date: August March 25, 2035 2020 Class 23-CB-3 P Principal Balance as of the Cut-Off Date: $149,937,994.00 224,290.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 4-A-5 Certificates will provide credit support to other Classes of Certificates, as described in the Pooling Agreement. WMALT Series 2005-7 9 Portion of the Class 24-CB-3 A-5 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,052,000.00 Class 24-CB-3 A-5 Certificate Interest Rate: 5.500% Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 24-CB-3 A-5 Principal Balance as of the Cut-Off Date: $149,937,994.00 1,052,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 CB-15 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 14,725,000.00 Class 2-CB-3 Certificate CB-15 ertificate Interest Rate: 5.5005.400% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2-CB-3 CB-15 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 14,725,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26January 29, 20052007. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. The Class 1-A-9 Certificates will provide credit support to certain Classes of Certificates, as described in the Pooling Agreement. WMALT Series 20052007-7 1 Portion of the Class 21-CB-3 A-9 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 2,367,500.00 Class 21-CB-3 A-9 Certificate Interest Rate: 5.500% Variable Cut-Off Date: August January 1, 2005 2007 First Distribution Date: September February 26, 2005 2007 Last Scheduled Distribution Date: August February 25, 2035 2037 Class 21-CB-3 A-9 Principal Balance as of the Cut-Off Date: $149,937,994.00 2,367,500.00 Exhibit A CUSIP ▇▇▇▇▇▇▇▇▇ Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another trust that owns a pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed byby This Certificate is issued by Washington Mutual Mortgage Pass-Through Certificates WMALT Series 2007-1 Trust. This Certificate represents ownership of one or more “regular interests” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is January 29, 2007. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. This Certificate is a Subsequent Exchangeable Certificate, as described in the Pooling Agreement. WMALT Series 2007-1 Portion of the Class 1-A-10 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $0.00 Class 1-A-10 Certificate Interest Rate: 5.500% Cut-Off Date: January 1, 2007 First Distribution Date: February 26, 2007 Last Scheduled Distribution Date: February 25, 2037 Class 1-A-10 Principal Balance as of the Cut-Off Date: $0.00 Maximum Initial Class 1-A-10 Principal Balance: $62,761,300.00 Exhibit A CUSIP ▇▇▇▇▇▇▇▇▇ Evidencing a beneficial interest in a trust that owns a pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by This Certificate is issued by Washington Mutual Mortgage Pass-Through Certificates WMALT Series 2007-1 Trust. This Certificate represents ownership of one or more “regular interests” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is January 29, 2007. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. This Certificate is a Subsequent Exchangeable Certificate, as described in the Pooling Agreement. WMALT Series 2007-1 Portion of the Class 1-A-11 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $0.00 Class 1-A-11 Certificate Interest Rate: 5.750% Cut-Off Date: January 1, 2007 First Distribution Date: February 26, 2007 Last Scheduled Distribution Date: February 25, 2037 Class 1-A-11 Principal Balance as of the Cut-Off Date: $0.00 Maximum Initial Class 1-A-11 Principal Balance: $62,761,300.00 Exhibit A CUSIP ▇▇▇▇▇▇▇▇▇ Evidencing a beneficial interest in a trust that owns a pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by This Certificate is issued by Washington Mutual Mortgage Pass-Through Certificates WMALT Series 2007-1 Trust. This Certificate represents ownership of one or more “regular interests” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is January 29, 2007. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. This Certificate is a Subsequent Exchangeable Certificate, as described in the Pooling Agreement. WMALT Series 2007-1 Portion of the Class 1-A-12 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $0.00

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 Principal Balance X Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 13,411,848.00 Class 2-CB-3 X Certificate Interest Rate: 5.500% 5.750%, applied to the Class X Notional Amount Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 X Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class X Notional Amount as of the Cut-Off Date: $13,411,848.00 Exhibit A CUSIP 93934F JF0 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 9 Portion of the Class 24-CB-3 Principal Balance A-3 Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 50,000,000.00 Class 24-CB-3 A-3 Certificate Interest Rate: 5.500% Variable, applied to the Class 4-A-3 Notional Amount Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 24-CB-3 A-3 Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class 4-A-3 Notional Amount as of the Cut-Off Date: $50,000,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 CB-7 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 68,674,000.00 Class 2-CB-3 CB-7 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2-CB-3 CB-7 Principal Balance as of the Cut-Off Date: $149,937,994.00 68,674,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26October 27, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 9 Portion of the Class 25-CB-3 A-1 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 13,211,400.00 Class 25-CB-3 A-1 Certificate Interest Rate: 5.500% Cut-Off Date: August October 1, 2005 First Distribution Date: September 26November 25, 2005 Last Scheduled Distribution Date: August November 25, 2035 Class 25-CB-3 A-1 Principal Balance as of the Cut-Off Date: $149,937,994.00 13,211,400.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26May 25, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 4 Portion of the Class 2-CB-3 CB-11 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 32,615,000.00 Class 2-CB-3 CB-11 Certificate Interest Rate: 5.500% Cut-Off Date: August May 1, 2005 First Distribution Date: September 26June 27, 2005 Last Scheduled Distribution Date: August June 25, 2035 Class 2-CB-3 CB-11 Principal Balance as of the Cut-Off DateBalance: $149,937,994.00 32,615,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26December 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company Trust or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT Series 2005-7 11 Portion of the Class 2-CB-3 Principal Balance X Notional Amount as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 13,411,848.00 Class 2-CB-3 X Certificate Interest Rate: 5.500% 5.750%, applied to the Class X Notional Amount Cut-Off Date: August December 1, 2005 First Distribution Date: September 26January 25, 2005 2006 Last Scheduled Distribution Date: August January 25, 2035 2036 Class 2-CB-3 X Principal Balance as of the Cut-Off Date: $149,937,994.00 0.00 Class X Notional Amount as of the Cut-Off Date: $13,411,848.00 Exhibit A CUSIP 93934F JF0 Class P Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by

Trust. This Certificate represents ownership of a “regular interest” in a “real estate mortgage investment conduit,” as those terms are defined in Sections 860G and 860D, respectively, of the Internal Revenue Code of 1986, as amended. The issue date of this Certificate is August 26March 28, 2005. Unless this Certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to the Company or its agent for registration of transfer, exchange, or payment, and any Certificate issued is registered in the name of Cede & Co. or such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest herein. WMALT The Class 1-A-2 Certificates will provide credit support to another Class of Certificates, as described in the Pooling Agreement. Series 2005-7 2 Portion of the Class 21-CB-3 A-2 Principal Balance as of the Cut-Off Date Evidenced by this Certificate: $149,937,994.00 1,638,000.00 Class 21-CB-3 A-2 Certificate Interest Rate: 5.500% Cut-Off Date: August March 1, 2005 First Distribution Date: September 26April 25, 2005 Last Scheduled Distribution Date: August April 25, 2035 Class 21-CB-3 A-2 Principal Balance as of the Cut-Off Date: $149,937,994.00 1,638,000.00 Evidencing a beneficial interest in a pool of assets consisting of beneficial interests in another pool of assets consisting of beneficial interests in another pool of assets consisting of, among other things, conventional one- to four-family mortgage loans formed by