817-5000, 817-2500, PRB25-IN, Pleatco, FC-2375, Filbur, Unicel, C-4326

817-2500 Waterway Spa Filter Cartridge 25 Sq. Ft. for 502-5010, 500-5010, 502-5050, 514-6559-DSG, 514-6589-DSG Dyna-Flo XL Skim Filters, and others. Fits for PRB25-IN by Pleatco, FC-2375 Filbur, Unicel C-4326, and many other brands.

Better than most all 50 sq. ft. cartridges because in the process of cramming 50 square feet of material into this size, once the cartridge is wet, the pleats stick together, 3 or 4 stuck together, then a usable gap or two, then 3 or 4 pleats stuck together, and a 50 foot cartridge becomes about 15 sq. ft. of USABLE filtration area. A 25 sq. ft. cartridge has more USABLE filtration area than a 50 ft. cartridge. Try a 25 sq. ft. next time you need a new cartridge filter and you will see the improvement it makes going to 25 sq. ft.

50 sq ft cartridges sound good in advertising, but in practical application, 25 sq ft. is a better choice.

Fits Waterway top load and inline filters originally equipped with a 50 sq. ft. cartridge or 25 ft. cartridge. For Rainbow Plastics filters, Waterway Above Ground Filters, and others using a 13-5/16" tall cartridge.

Measures 13-5/16" x 4-15/16" (5") and bottom opening is 2-1/8" diameter. FC-2390 PRB50-IN.