Torque wrenches are hand or power tools that are used to apply a specific amount of torque to a fastener. These adjustable-torque tools are primarily used to prevent over- or undertightening of fasteners. Both over- and undertightened fasteners are hazardous in different ways, but both could result in the eventual failure of the fastener.
Torque wrench types include click, dial, beam, deflecting beam, or electronic. A wrench's application is largely determined by the range of torque it is designed to deliver. For example, wrenches for use in automotive or heavy industry applications must be capable of delivering high torque, while tools for use in lighter industries have lower torque capabilities.
A click-type torque wrench.
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