SP Air Corporation SP-1158 Impact Wrenches are ideal for a wide variety of fastener turning jobs in both truck shops and industrial fields. This compact, high powered impact wrench is preferred for tasks including spring or pinion nut work, truck pad removal, major engine teardowns, and much more. The single dog clutch mechanism delivers up to 1,200 ft./lb. of maximum torque with a specially designed regulator system that allows mechanics to adjust power output in one direction while maintaining full power in the opposite direction