Pleatco PA106-4 Replacement Cartridge for Hayward SwimClear C-4025, 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 25-1/2-by-3-by-3-inches Made in the USA