Unicel 4CH-935 Replacement Filter Cartridge for 35 Square Foot Waterway Diameter: 4 15/16-inch; length: 9 1/4-inch Top end cap: v-groove semi-circular handle, 0-inch inner diameter; bottom end cap: 2-inch female sae thread, 0-inch inner diameter Pleat count: 219; filter media: 3-ounce reemay 2033; filter area: 35 square feet Get more efficient filtration and better water clarity with Unicel filters Longer time between cleanings; meets oem specifications