[Premium Quality Material and Multi-Layer Density Tech] Complying strictly with FDA standard (CFR-Part 177) and tested by independent third 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. The polypropylene construction provides superior chemical resistance and is not prone to bacterial attack. [Highly Activated Carbon Block CTO 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. [Exceptional Filter Life] This filter pack can filter up to 50,000 gallons depending on the use and feed water quality. Replace the filters every 3-6 months to achieve optimal performance. 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. [Great Compatibility] This filter pack consists of 1x 10"x4.5"Sediment Filter(FP15B) and 1x 10"x4.5" CTO filter(FC15B). Fits standard 10" whole house water filtration systems. Individually sealed for freshness. [Peace-of-mind Customer Support] Your risk-free shopping experience is backed by a 30-day money-back guarantee, extended manufacturer warranty, and lifetime tech support from iSpring in Atlanta, GA at (678) 261-7611.