Pleatco PRB100 Replacement Cartridge for Dynamic Series II and III RTL/RCF-100, Series V-DSC-100, 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 26-1/2-by-2-1/8-by-2-1/8-inches Made in the USA