Cordless impact wrenches combine a hammer-like impact and high rotational torque to drive and remove fasteners. They initiate impact force when they detect resistance from the fastener and deliver the impact in bursts that minimize the stress felt when operating the tool. Impact wrenches typically have a square drive and use impact-rated sockets. These battery-powered tools don't require access to a wired power source and don't have power cords or air supply hoses that can cause tripping hazards.