Filter means material placed in the useful beam to preferentially absorb selected radiations.
Plastic means material which contains as an essential ingredient a high polymer such as polyethylene terephthalate, high density polyethylene, Vinyl, low density polyethylene, polypropylene, polystyrene resins, multi-materials like acrylonitrile butadiene styrene, polyphenylene oxide, polycarbonate, Polybutylene terephthalate;
Metal means precious metal, including, without limitation, gold, silver, platinum, palladium, rhodium, iridium, and ruthenium.
Filtration means a process for removing particulate matter from water by passage through porous media.
Fiber means a glass strand or strands which is/are protected by a color coded buffer tube and which is/are used to transmit a communication signal along the glass strand in the form of pulses of light.