With the specifications as Filbur # FC-1220, Pleatco # PA225-4, Unicel # C-4325 and OEM # CX225RE this replacement filter cartridge can bear the top load of 25 sq. ft. This 11 7/8 inch long and 4 5/8 inch wide filter cartridge has 2 1/16 inch holes at its top as well as bottom. It provides you pure water for your Haywards CX225-RE, American Commander 11, Emerald Spas, MicroStar-Clear C225, Apollo Spas, Sonoma Spas, etc. It is a great quality filter cartridge that provides you pure water. It is very easy to install and gets replaced without any obstacle.