Baleen Filters 25 sq. ft. Pool Filter Replaces Unicel C-5624, Pleatco PJW25, Filbur FC-1305-Pool and Spa Filter Cartridges Model: AK-4027 Media Area 25 sq ft, 5 3/4" OD, Open Hole: 2 1/8" Top, Open Hole: 2 1/8" Bottom, 11 7/8" Long, AK-4027 Baleen Filters are made from Durable and Efficient USA Made Reemay Fabric - Washable Fabric Extends Your Filter's Life 25 sq. ft. 5000 Series Cartridge for Jacuzzi Whirlpool Bath - Avanza, Celeste, Meridian, Sienna, Virage Filter, replacement of Unicel C-5624, Pleatco PJW25 Baleen Filters Top:Open Hole: 2 1/8" Bottom: Open Hole: 2 1/8" Guaranteed Perfect Fit - Extremely Durable - Wash & Reuse - Most Energy Efficient - Withstands High Pressures & Temperatures