Pleatco for Dynamic Series I RDC-25, I RDC-25S, Dynamic Series II and II RTL/RCF-25, Dynamic Series IV-DFM, DFML, Waterway 25 In-Line, (MICROBAN) Replacement filter for pool and spa cleaning systems for dynamic series I rdc-25, I rdc-25s, dynamic series ii and ii rtl/rCF-25 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-4326 and filbur FC-2375; made in usa; microban inhibits the growth of stain and odor causing microbes like bacteria and algae Measures 5-inches in diameter by 13-5/16-inches in length and 2-1/8-inches of top and bottom hole diameters