Unicel C-7470 80 sq. ft. Clean and Clear Plus Waterway Crystal Water Replacement Filter Cartridge

80 Square Foot Clean & Clear Plus, Waterway Crystal Water. Replacement for: Pentair Pool Prod R173573 (Note: Four 80 Square Foot cartridges required.); Pentair Pool Prod - Pac Fab Replacements 178580 (Note: Four 80 Square Foot cartridges required.); Waterway Plastics 817-0081 (Note: Four 80 Square Foot cartridges required.)