Poolmaster 12834 Replacement Filter Cartridge for Dimension One 75 1561-12 Filter The corresponding Pleatco number is PDO75P3and the corresponding Unicel number is 7CH-975 The top of the replacement filter cartridge is semi-circle handle and the bottom is 1-1/2 male thread SAE Break-resistant bands keep pleats separated for greater flow, filtration and add longer life to cartridge High quality spun bonded polyester material for exceptional water filtration Premium grade polyurethane and plastisol end caps