well, judging by what i saw at the autoshow...it appears as though the rotors are 15", two piece drilled rotors...the calipers appear to be multi-piston, possibly four, as the "outside" looks as though it has a shape which would nicely hold two pistons, and i figure that the outside would be the same...however, this braking system is elaborate, and would be very expensive. one reason that i question this whole system making it to production (on a reasonably priced car, which the challenger may not be) is because the cost for one, and also based on the fact that dodge has said that it wont come with some of the concept items, like the flowmaster exhaust system.