A PermaCoil® (often referred to by the trade-name HeliCoil^®) is a thread repair insert  used to create internal screw threads to accommodate screws and bolts. Most users are trying to repair a damaged thread back to the original size. Other users may be trying to change the threading to something more standard.

As the name suggests, a thread repair insert is a coil that is installed into a the original hole (after being re-drilled and taped with a special drill and tap set). When properly installed, these inserts provide high-quality, wear resistant, permanent internal threads. In their most common application, thread repair inserts are ideal to repair stripped threads (hence the name thread repair inserts). Thread inserts are also commonly used in new part designs because of the many benefits that they offer.

The PermaCoil® kits provide the inserts as well as the the special STI tap that matches the external insert so when installed it mates properly.  You also get the break-off tool to seat the insert. The back of the package tells you what size drill bit you need, and we can supply that too (ask your Hardware Everywhere representative what size you need) -- they are not included because different applications require different types of drill bits (high-speed, cobalt, titanium, all in different lengths.)