Pleatco PCH75 Replacement Cartridge for Christal Pools England, 1 Cartridge Replacement filter for pool and spa cleaning systems 50% open ABS free flow cores maximize water flow through REEMAY filter media Antimicrobial end caps resist chlorine degradation and provide support to filter material for a longer life span 24-1/8-by-5-3/16-inches Slip with closed top Made in the USA