Pleatco PAS50-F2M-M Replacement cartridge for Upgrade to Newer Artesian Spa Models (MICROBAN), 1 Cartridge Replacement cartridge for upgrade to newer artesian spa models 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 and filbur; made in usa; microban inhibits the growth of stain and odor causing microbes like bacteria and algea Measures 7-1/8-inches in diameter by 7-9/16-inches in length and 2-inches MPT bottom hole diameter