This is the adapter which connects to the cylinder head to media-blast the carbon buildup off the intake valves. This is a Genuine BMW part (Part #81 29 2 208 038) that has only been used once. A media blasting tool is inserted into a small hole at the front of the tool, and a shop vac is connected to the tailpiece, pulling all the media and carbon out of the intake port and keeping your engine nice and clean.

Works great, I used it many years ago and the car drove like new after I did the work. My Mini is gone now, so this should go to someone who can get some good use out of it.

Listing new online currently for ~$70, I'm asking $40 + shipping. PM me if interested.