This air impact wrench has a lightweight composite body to reduce strain. The composite impact wrench delivers 820 ft. lbs of bolt breakaway torque to get tough jobs done fast. Twin-hammer impact mechanism for high torque with less vibration. 1/2" 820 ft. lbs max torque 8500 no load RPM 4.6 CFM at 90 PSI average air consumption Twin-hammer impact mechanism for high torque with less vibration 1/4" air inlet 3/8" minimum hose.