Pneumatic Sander, General Duty, High Speed, 0.4 HP, Pad Size 3, 4, Or 5 In, Arbor Hole 7/8 In, Spindle Size 7/16 In, Free Speed 15000 RPM, Average CFM @ 15 Second Run Time 3.5, CFM @ Full Load 21, Required Pressure 90 PSI, Air Inlet NPT 1/4 In, Min Hose Size 3/8 In, Length 7 5/8 In, Aluminum Housing, Variable Speed Lever Throttle, Includes Spindle Lock Key, Three Sanding Discs