Designed as the official filter replacement pack for iSpring WGB21B whole house water filtration system, this filter pack consists of two 10 in. X 4.5 in. Sediment Filters(FP15B) and two 10 in. Fits standard 10 in. Whole house water filtration systems as well. Being capable of filtering up to 50,000 Gal. Depending on the use and feed water quality, included fine PP sediment filter and premium quality CTO filter not only bring clean and refreshing water to every faucet in your home, but also help prolong the lives of your water-using appliances and protect plumbing from sediment and scale buildup. Complying strictly with FDA standard (CFR-part 177) and tested by independent 3rd party against NSF/ANSI standard(NSF/ANSI 42) for material safety and water quality. ISpring premium 5-micron polypropylene sediment filter (FP15B) captures dirt, sand, silt, dust, rust and scale particles and extends the life of CTO carbon block filter. Using high quality coconut shell carbon and highly compact fabrication tech, iSpring CTO filter(FC15B) knocks out cloudiness as well as bad tastes and odors, removes up to 99% of chlorine and is highly effective on organic compounds like herbicides and industrial solvents and other contaminants like trihalomethanes. Sediment filters (FP15B) and two 10 in. CTO filters (FC15B) included. Official replacement filter pack for iSpring WGB21B whole house water filtration system. Whole house water filtration systems. Individually sealed for freshness. Peace-of-mind tech and CS support from Atlanta, GA. How Can We Help?