They look like this:

Now, that cap looks very familiar but the rotor looks a little different. Here's a picture of what they say an M3 rotor should look like. This also matches the ETK diagram:

So, I recall people talking about spring-loaded this, and gapped that. What I want to know is: are these rotors compatible? It looks like they mount in completely different ways. If not, I cannot, for the life of me, find any Volvo rotors that look remotely similar to the BMW one above.

I do notice that they always list another PN for M3 rotors but nobody has a picture of that one.

So, can anyone straighten this out for me?

Thanks,
Jon