I have a torque screwdriver from Harbor Freight (Quinn brand) and find it somewhat difficult to hold back the adjustment ring when adjusting high torque values. It also has a tendency to pinch my hand. This tool fits over the adjustment ring (which is a hex with rounded corners) and makes it easy to hold it back while making an adjustment. You could also put it in a vise if desired. Printed with PLA, 15% infill, hex side down with support.