Aqua Kleen AK-6056 Unicel Replacement Filter Cartridge for Swimming Pool and Spa 105 sq. ft., 7" OD, Open Hole: 2 15/16" Top, Open Hole: 2 15/16" Bottom, 25 5/8" Long, AK-6056 Exact Fit for Unicel: C-7496 Exact Fit for Pleatco: PPF105-4 Exact Fit for Filbur: FC-2180 Guaranteed Perfect Fit - Extremely Durable - Wash & Reuse - Most Energy Efficient - Withstands High Pressures & Temperatures