- Repair damaged internal threads.
- Clean dirty internal threads.
- Cut new internal threads.
- Buy a T-handle if not included.
- Available as a kit with a matched drill bit.
- Consider a full tap, die and drill set.
If you've had to drill out a sheared shaft these are useful to clear the remnants from the hole. If the thread is damaged you can sometimes shave off the damage to restore it, otherwise drill it larger, tap a new thread and use a large shaft for the repair (if the assembly will allow it).