Poolmaster 12837 Replacement Filter Cartridge for Caldera 75 New Style 1019301 Filter The corresponding Pleatco number is PCD75N and the corresponding Unicel number is C-7375 The top of the replacement filter cartridge is semi-circle handle and the bottom is open 2-11/16 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