This Replacement filter cartridge replaces Unicel # C-4312, Pleatco # PA12 and Filbur # FC-1210 and complies with the OEM # C120RE specifications. This filter cartridge can bear the top load of 12 square foot and best fit for Hayward C120-RE, MicroStar-Clear. With its 11 7/8 inch length and 4 5/8 inch width the filter cartridge has 2 1/16 inch holes both at the top as well as bottom. With this high quality filter cartridge you get pure water free from germs and sand.