The Unicel C-4606 R is a compatible replacement for the following pool and spa water filter cartridges:
The Unicel C-4606 Comp. Replacement Pool Filter is a pool filter cartridge replacement constructed with 5 sq. ft. of pleated Reemay filter media for the reduction of contaminants in swimming pool and spa water. This compatible Unicel spa filter, also known as the Filbur FC-3709, measures 4 1/4" x 8" with 1 5/8" Open top and bottom styles.