For Pentair Clean & Clear Plus 520 Sq. Ft. Replacement Cartridges
These are Unicel C-7472 / Filbur FC-1978 / FC-3433 / PleatCo PCC130 / X15-ULT-A7-Q4 Replacement Cartridges that are equivalent to R173578 not Pentair.
Cartridge Size 7" X 32 1/16"
For models dated after 11/98