It is nicely machined of aluminium and polished. The special shape gives a very good grip. Just lube up the rubber with a bit of soapy water and slip it on. It will stay put. Length: circa 7,5 cm, diameter: circa 2,7 cm
You can also use a BMW emblem.
It is made of...
This oil filler plug with Allen tool looks absolutely great...
Made of high-quality aluminium and fits all four valve twins...