Pentair 24850-0016 Clamp Retaining Ring Replacement Sta-Rite System 3 Pool and Spa Filter Clamp retaining ring replacement Fits Pentair Sta-Rite System 3 SM-Series modular media filters Also fits Pentair Sta-Rite System 3 SD, SS-Series D.E. and sand filters Measures 1-inch length by 1/4-inch height by 1-inch width