Pleatco PVT50W Replacement Cartridge for Vita Spa Filtration Filter, 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 7-1/8-by-1-7/8-by-2-3/8-inches Keyed Made in the USA