There is a drilling in the side of the plug in which you can put a size 3 Allen key or a Torx key T10 (usually found in the your BMW toolkit) in order to fit and remove it.
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Also referred to as oil filler cap.
These covers for the open holes of the suspension mounting...
These crash protectors for forks are made of cnc lathed...
Aluminum protective cover for the safety switch on the side...