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.
Fold Away Lever Kit by Magura (clutch and brake lever)....
Oil filler plug Torx, made of high-quality aluminium....
This adjustable foot brake lever makes it easier to operate...