Baleen Filters 35 sq. ft. Pool Filter Replaces Unicel C-4335, Pleatco PRB35-IN, Filbur FC-2385-Pool and Spa Filter Cartridges Model: AK-3015-2, 2-pack Media Area 35 sq ft, 4 15/16" OD, Open Hole: 2 1/8" Top, Open Hole: 2 1/8" Bottom, 9 1/4" Long, AK-3015 Baleen Filters are made from Durable and Efficient USA Made Reemay Fabric - Washable Fabric Extends Your Filter's Life 35 sq. ft. EZ Twist Top Mount Skim Filter with Top Load Pressure for Bullfrog, Hydro Pool, Hydro Spa, Infinity, Sun Ray Cartridge, replacement of Unicel C-4335, Pleatco PRB35-IN Baleen Filters Top: Open Hole: 2 1/8" Bottom: Open Hole: 2 1/8" Perfect Fit - Extremely Durable - Wash and Reuse - Most Energy Efficient - Withstands High Pressures and Temperatures