This is a magnetic sump plug to fit the BMW 3-Series E90 330d

Engine: M57D30TU2 and M57D30OL

Year: 09/2006 - 06/2012

It has a M12 x 1.5 thread

Plug Material: Aluminium 

Washer Material: Copper

Item includes one black plug and a copper washer.

The magnet attracts metal filings that will naturally occur in the oil, it's a great way to monitor the condition of your engine over time.