WARNING: This page is about a different car, the 2013 BMW X5 M, 2012 BMW X5 M, 2011 BMW X5 M, and 2010 BMW X5 M. However, it is still accessible from the selected car via links, so may be relevant.
0492064 324007 Connector MW
NOTE:
(Connection piece M18 x 1.5) For screwing into pressure regulator / Model series: E32, E34 [Released]