A backup wrench will prevent rotation of the bolt or stud when the nut is being tightened. A back-up wrench prevents the bolt from rotating during torquing. During the tightening of the bolt , the back-up wrench does not have to be held by hand, which increases safety. Although the backup wrench will be locked in place after tightening, it can be easily removed by loosening the small hex bolt. Compared to a manual method, this variant is many times safer, especially when working at higher torques.