Pentek S1-BB # 155405 S1BB Big Blue Whole House Sediment Replacement Water Filter Cartridge Compatible With Culligan, Ametek, US Filter, Plymouth, Kleen Plus, American Plumber, Bruner & Many Other Brands. S1-BB Big Blue 20 Micron Pleated Cellulose Sediment Water Filter. 10" long X 4 1/2" diameter. 8 per case, sold individually. Ametek # 155405 S1 series cartridges are economically priced and highly effective at reducing sediment particles down to 20 micron in size. Whole house or point of entry POE filtration to filter out sand, silt, dirt and rust particles that can restrict and plug finer water filters, screens or equipment. Order a case and save even more.