Draper 51766 SPC14-18MM Expert 14-18mm Spark Plug Thread Chaser

Expert Quality spark plug chaser, which covers two common sizes, 14mm and 18mm spark plugs threads.
Capable of fulfilling two purposes on motor vehicles:

1. It cleans spark plug threads in the head, by getting rid of excess grunge, dirt and other particles that become embedded in the thread - This action results in a longer thread life and more efficient operation of the spark plugs.
2. It's used to restore damaged threads, which have the potential to cause cross threading, potentially making spark plugs immovable.

For these reasons, this spark plug chaser is a handy tool to have in any professional mechanics toolbox.