This Replacement Filter Cartridge replaces Unicel # 4625, Filbur # FC-2370 and OEM # 17-2325. It bears the top load of 25 sq ft and provides you neat and clean water for your Pentair Pool Products-Rainbow Pl, Waterway Plastics, Heldor Spas. Hydro Pool Industries, Haughs, Serenity spas, J.E.M. Spas, Niagara Whirlpool, Warm Spring Spas, Sequoia Design, Associated Leisure Products, Esther Willams, Blue Pacific, Alps Spas, Aries Spas, etc. This both side open through 2 1/8 holes is 13 5/16 inch long and 4 15/16 inch wide. It is an excellent quality replacement filter is very easy to replace.