This part is listed by BMW as BMW part number 11367836238 (11 36 7 836 238) and is described as the o-ring that seals the solenoid to the VANOS unit on E60 M5 and E63 M6 S85 V10 engines.
This is a Genuine BMW VANOS o-ring with a two year warranty. Buying a Genuine part will usually be more expensive than an OEM or aftermarket brand but you are assured that it meets BMW's designs for fitment, performance, and longevity. It will also be the very latest design, incorporating any updates or revisions that an aftermarket brand typically will ignore.
For full BMW fitment information or for assistance from one of our BMW experts, we recommend calling us at 877-639-9648.
BMW Fitments:
5 Series
E60 / E61 (04-10) > M5
6 Series
E63 / E64 (04-10) > M6