iSpring FC15BX4 4.5" x 10" Carbon Block Water Filter Replacement Cartridge, 5-Micron Universal Coconut Shell High Capacity CTO Filter for Under Sink and Whole House Water Filtration Systems, Pack of 4

[Premium Quality Material] Using high-quality coconut shell carbon and highly compact fabrication tech, this highly activated carbon block CTO(Chlorine, Taste, and Odor) filter cartridge is designed and produced to achieve maximum filtration efficiency and filter life for 10" Whole House Water Filtration Systems. Free of surfactants, binders, and adhesives. No leaching carbon ash. [Exceptional Filtration Performance] 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. Steady flow and high absorption. [Long Filter Life] Each cartridge filters up to 50,000 gallons depending on the use and feed water quality. Replace the filter every 6 months or every 50,000 gallons of water for optimal performance, depending on the quality of source water and daily water consumption. [Great Compatibility] Fits standard 10"x4.5" filters. Official 2nd stage Carbon Block replacement filter cartridge for iSpring under sink water filter US21B and whole house water filtration system WGB21B; 1st stage for WGB21BM and WGB21B-PB. All 4 cartridges are individually sealed for freshness. [Peace-of-mind Customer Support] Your risk-free shopping experience is backed by a 30-day money-back guarantee, extended warranty upon registration, and lifetime tech support from iSpring in Atlanta, GA.