Pleatco PRB25SF-JH-PAIR Replacement Cartridge for Dynamic Series IV, Model DSF, DFML-25C, Waterway, 1 Cartridge Replacement cartridge for dynamic series IV 50 Percent 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 Replaces unicel C-4405 and filbur FC-2387; made in usa; microban inhibits the growth of stain and odor causing microbes like bacteria and algea Measures 5-inches in diameter 6-5/8-inches in length and 2-1/8inches of top and bottom hole diameters