The Waterway ClearWater Above-Ground Cartridge Filter FC1007 is a replacement cartridge filter for 100 sq. ft. deluxe filter systems 522-5127-3S, 522-5147-3S, 522-5127-6S, 522-5147-6S, 520-5127-3S, 520-5147-3S, 520-5127-6S, 520-5147-6S, 520-5127. Specifications: Cartridge replacement for 522-5127-3S, 522-5147-3S, 522-5127-6S, 522-5147-6S, 520-5127-3S, 520-5147-3S, 520-5127-6S, 520-5147-6S, 520-5127