I'm kind of in a tough spot. The car is at Rennwerke and I'm up in Canada, about 1,000 miles away. I ordered the wheels from Mariani Motorsport and had them delivered, and I've never seen the wheels in person. The only photos I have are what I've posted and getting Cheech to even send those was a big ask. Anyway, there's a photo showing "ET15" on the back of the wheel: