Omnifilter, 20", Heavy Duty Filter Cartridge, Fits Omnifilter BF55 Housings, Extra Large Capacity, High Flow With Minimal Pressure Drop Granular Carbon Taste & Odor Filter For Use On All Water Well & Chlorinated, Reduces Chlorine Taste & Odor, Other Tastes & Odors, Sediment, Dirt & Rust Particles.