Pentair 076033 Clamping Band Knob Replacement Pool and Spa D.E. Filter Clamping band knob replacement Fits Pentair SM & SMBW 2000 and 4000-series D.E. pool/spa filters Also fits Pentair Nautilus Plus D.E. pool and spa filters Measures 3-inch length by 1-1/2-inch height by 1-1/2-inch width