This drain plug wrench is designed to use with Pentair Nautilus Plus pool and spa D.E. filter models NSP36, NSP48, NSP60, NSP72. Also compatible with D.E. FNS filter models FNSP 24, FNSP 36, FNSP 48, FNSP 60. Also compatible with Clean & Clear Plus filters models CCP240, CCP3201, CCP4201, CCP5201. Measures 10-5/8-inch length by 1-inch height by 2-1/4-inch width.