BMW Motorrad – Spark plugs Tool :

Safe and easy removal of thespark plug cap(or HT coil) without risk of damage to the coil.
For good reasons, the originalspark plugconnector should not be removed with pliers or similarly crude tools: the ignition coil integrated into the cap can easily be damaged which will prevent you from continuing your journey.

The original extractor often breaks with caps that are stuck and it also bends easily. With a extraction handle and additional transverse hole to pull out those stuck caps.