This Replacement filter cartridge replaces Unicel # C-4346, Pleatco # PSI45-4 and Filbur # FC-2670 and it meets OEM # C4346 specifications. This 17 ¾ inch long and 4 15/16 inch wide filter cartridge is closed from its top while has 2 1/8 inch open hole at the bottom. It is capable of handling the top load of 45 square feet and is best fit for Santanna, Conger Bros., Fountain Valley Spa. It provides you clean and clear water for your pools and spas keeps them free from germs and sand. It can installed very easily without any hassle at all.