Easily installs on 1/2 inch or 3/4 inch main cold water line, reduces dirt, sand, silt, rust and scale particles to extend life of household fixtures and appliances. Constructed of opaque polypropylene for added durability. Dynamic sealing, self-cleaning O-ring prevent leaks and clogging. Use with #CW-MF, S1A, CW-F or P5 filter cartridges, #OR-34 replacement O-ring, #SW-2 filter housing wrench #UB-1 mounting bracket. NSF International tested and certified.