The Freeflow FF-100 R is a compatible replacement for the following spa filter cartridges:
The Freeflow FF-100 Comp. Pool & Spa Filter Cartridge is a spa filter with 25 square feet of media area and a Closed Knob Handle. This compatible Freeflow filter measures 4 15/16" x 6 5/8" with a 1 1/2" MPT bottom style. With this pool filter you will be able to improve the water quality in your swimming pool or spa.