Replacement filter cartridge used for a pool, hot tub or spa. Measurements: Length:  26" Diameter:  7" Top Opening:  3" Bottom Opening:  3" Popular brand part numbers: Unicel: C-7471 Filbur:  FC-1977 Pleatco:  PCC105 Features: Free Flow Core 105 Square feet of filter media Made by Guardian Filtration Products in the USA   Alternative filter names:  American Products 817-0131,  R173476, 178584,  SD-00073,  56627900,  SD-00842,  R173576,  CCP420,  CC420-after 11/98,  CC520-before 11/98,  Pentair Clean & Clear Plus 420,  American Quantum 500,  160301, CC7471,  570-0425,  817-0106,  R178584, 17-175-2124,  17-175-2125,  R173219,  570-0425-07,  PCC7296,  20503,  FC-6470,  PCC 105,  PCM125,  PCM 125,  PWW105 Used in pools/spas made by:  American Products,  Pac Fab,  Pentair Pool Products,  Waterway Plastics and other manufacturers