A device which shows the force of torque with which a screw or nut is being tightened. It allows one to set screws exactly at a predetermined torque without any effort. A wide range of models from different manufacturers are available. The most common models are listed below. Preset Type: Suitable for high efficiency mass production. By presetting the wrench you can tighten bolts to a desired torque every time. To operate, you first pull the handle until it clicks to the set position. Then you tighten the bolt until the resistance of the wrench stops. When you release the wrench, it is automatically set for the next operation. No need to refer to a dial or meter during use allowing you to increase work speed substantially. For use with a socket wrench.