This plug drain cap is designed to use with Pentair Warrior, EasyClean aboveground pool and spa D.E. filters and also compatible with Pentair Clean & Clear/Predator, Clean & Clear Plus pool and spa cartridge filters. Also fits Pentair EasyClean, FNS Plus, Warrior pool and spa D.E. filters. Includes o-ring. Measures 2-3/8-inch length by 1-1/4-inch height by 2-3/8-inch width.