The result was a combination screw driver wrench and tap or reamer wrench. The drawing illustrates successive stages in the evolution of the tool.

Most of the time, you’ll be able to easily walk to your box, grab your tap wrench and a common-thread tap and thread your widget. Sometimes, though, the thread you’re looking for is an oddity ...

The tool used for this operation is often a T-handle tap wrench. It's an excellent tool to repair damaged threads, but it has one problem: it requires a lot of space: This is fine if the thread ...