Made from resin-impregnated cellulose and polyester fibers, the ECP1-20BB Pentek Big Blue Filter Cartridge is a superior quality water filter cartridge from Pentek that reduces sand, dirt, silt, rust, and scale particles in residential and commercial water. It features high dirt holding capacity, high flow rates while maintaining very low pressure drop. Featuring nominal filtration rating of 1 micron and temperature rating of 40?F to 125?F, this water sediment filter is well-suited for whole-house sediment filtration. It has initial pressure drop of less than 1 psi at a flow rate of 20 gpm i.e. <0.1 bar @ 76 L/min. This 20" x 4-1/2" (508 mm x 114 mm) ECP1-20BB is used to treat rust filtration, sediment filtration and various applications, on both city and well water.