1/2" Super-Duty Air Impact Wrench Bring out the big for tire changing, and other heavy automotive and truck work with Ingersoll Rand. The 1/2 in. Super-Duty Air Impact Wrench mechanism pumps out 500 ft.-lbs. torque at a free speed of 7,000 RPM to get the job done fast. . Twin Hammer Plus mechanism pumps out 500 ft-lbs. of maximum torque at a free speed of 7,000 RPM Powerful, with smooth, balanced blows Pressure Feed Lubrication System automatically greases the impact mechanism requiring less maintenance . 1/2 in. Super-Duty Air Impact Wrench - 244A 244A