This part is listed by BMW as BMW part number 07119963072 (07 11 9 963 072) and is described as a 13.5x10mm copper gasket seal ring found in various places on many BMW models.
This is a Genuine BMW seal 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.