Sta-Rite 2 System 3 25022-0203S+25021-0202S Swimming Pool Filters Set S8M150 Replacement Cartridge combo pack for Sta-Rite S8M150 pool filters Contains one large and one small S8M150 replacement cartridges Cartridges incorporate the best filtration technology for balanced flow and care-free operation Small S8M150 Cartridge Model: 25021-0202S Large S8M150 Cartridge Model: 25022-0203S