Unicel SC3-SR100 Replacement Filter Cartridge for 102 Square Foot Sta-rite 100TX, 100GPM-TX, 100TXR, T-100TX, T-100TXR, PTM100 Diameter: 8 11/16-inch; length: 25 11/16-inch Top end cap: open, 4-3/16-inch inner diameter; bottom end cap: open with 12 concentric slots, 4-3/16-inch inner diameter Pleat count: 195; filter media: 3-ounce reemay 2033; filter area: 102 square feet Get more efficient filtration and better water clarity with Unicel filters Longer time between cleanings; meets oem specifications