Cheap Lee Valley 3/8 M10 Insert Nut Driver

For use in a drill or drill press, this insert nut driver has a standard 1/4″ hex shank. The shaft does not engage the insert threads, and the insert is held in place with a ball detent.

The insert is driven by wings that engage the insert slot. The wide shoulder acts as a stop, contacting the work when the nut is sunk just below the surface.