This is the Genuine BMW rod bolt used on the S65 V8 in the E90/E92/E93 M3 and the S85 V10 in the E60 M5 and E63 M6. Each connecting rod uses two bolts and they must be replaced any time a bolt is removed from the rod. They stretch when tightened and cannot be re-used.
This is a Genuine BMW rod bolt 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.
A stronger and re-usable ARP rod bolt is also available. Some M3 owners favor the ARP to reduce the potential for rod bore distortion. BimmerWorld does not have data to favor one bolt over the other but a stronger bolt is likely better and being able to re-use the ARP is more desirable.
E90 / E91 / E92 / E93 (06-13) > M3
E60 / E61 (04-10) > M5
E63 / E64 (04-10) > M6