The Unicel C-5635 R is a pool and spa water filter cartridge that is the correct compatible replacement for the following filters:
The Unicel C-5635 Comp. Spa Filter - Jacuzzi CFR-37 has an outer diameter of 5 inches, with a length of 13 5/16 inches. This Unicel pool filter has an open top and bottom with both having diameters of 2 3/8 inches. This Unicel C-5635 filter contains 37 square feet of filter media.