Kevin Bird is the contact. Back a while I called Quaife to see if they had a diff for our cars and they tole me Kevin Bird had become the distributor for all MB diffs. He had done a great job for them with BMW's and was moving all MB applications to him. Quaife has been around a long time and their diffs are common in road race cars. I had heard the Wavetrac was pretty much a copy of the Quaife. they are very similar and priced about the same. He was willing to drop the price 20% for a group buy of five. He wanted to ship to one person in the US and then shipped to individuals from there. When I heard about the wavetrac I decided to wait that out as i didn't want to mess that up because at the time there was still people needed to get to 20. Now that their is a waiting list just to get on the list, it may be time to have an additional supplier.