The GearWrench 81 Series Air Impact Wrenches includes the 3/8” Drive Air Impact Wrench, No. 88130, the 1/2” Drive Air Impact Wrench, No. 88150, and the 3/4” Drive Air Impact Wrench, No. 88170. The GearWrench 81 Series Air Impact Wrenches feature a twin-hammer impact mechanism that operates at reduced sound levels due to the "highly effective" muffler. They also offer a lightweight design and are constructed for optimum comfort. The wrenches come with a two-year warranty.