Abstract: The benefit of and the practical side of the improvement, by adding the retaining shoulder to the jaws of the wrench on the box-end and the open-end parts of the wrench, is the decline of slippage and limited loss of control of the tightening or removal procedure, producing an ease of maintaining one's position on the bolt or nut when the vibration of an impact wrench is incorporated or manual procedures, no matter how precarious the position or how open the position is to the mechanic, technician, or untrained shop help. This Backup Wrench does not allow the nut or bolt to skip through the jaws of the wrench whether on open-end or box-end as it has a built-in stop. The stop holds the nut but alls the bolt to protrude without affecting the Backup Wrench's position. Sizes range from ¼? on up to any size desired—American or Metric.