OEM# 178580, 160340, CCP320, R173573, Unicel# C-7470/C7470, C-7470RA, Pleatco# PCC-80/PCC80, PCC80-M, PCC80-PAK4, PWW80, Filbur# FC-0675, FC-1976/FC1976, FC-1976M, FC-1976P, FC-6465, Aladdin# 18005. Number of Cartridges: 4. Outside Diameter: 7 in. Inside Diameter: 3 in. Length: 20 in. Made in USA with high quality filtration media that was made specifically for durability and cleanability. Includes support bands around each cartridge element. NOTE: This is a compatible aftermarket replacement part. The manufacturers’ names and part numbers have been used for reference purposes only. Optimum Pool Technologies Inc is an independent brand.