Angle Grinder Wheel Diameter 4 1/2 in Horsepower 1.1 hp For Wheel Type Type 27 Max Speed 12 000 RPM Air Inlet 1/4 in NPT Female Air Inlet Connection Size 1/4 in Air Inlet Gender Female Air Inlet Type NPT Lever Type Safety Lever Spindle Thread Size 3/8 In.-24 Reach Standard Reach Duty Heavy Duty Variable Speed Yes