Pleatco PJW30-4 Replacement Cartridge for Jacuzzi Whirlpool 30, 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 14-7/8-by-3-9/16-by-3-1/2-inches Made in the USA