Hi Archeon,
The following page on the Autoleads website has some more information:
http://www.autoleads.co.uk/Cat%201/bmw.html
Alternatively, the technical guy at Autoleads is called Derek McCrory, and he is always willing to answer queries on this kind of subject. If you want to give him a call, the number is:
+44 (0)1420 476767.
Be aware that Autoleads do not deal directly with the public, so you will still need to find a distributor who will sell you what you need, e.g. Halfords in the UK.
Andy.