Pleatco PA75SV-PAK4 Replacement Cartridge for Hayward C-570, SwimClear C3020, Super-Star-Clear C3000, C3000S Sta-Rite PRC 75, Pack of 4 Cartridges 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 Length 19  inches, Top Hole 3 inches, Bottom hole 3 inches Made in the USA