Unicel C-7630 Replacement Filter Cartridge for 30 Square Foot Skim Filter Diameter: 7-inch; length: 11 3/4-inch Top end cap: semi-circular handle, 0-inch inner diameter; bottom end cap: open, 3 0/0-inch inner diameter Pleat count: 110; filter media: 4-ounce reemay 2040; filter area: 30 square feet Get more efficient filtration and better water clarity with Unicel filters Longer time between cleanings; meets oem specifications