These cross-drilled rotors are BMW factory-fitted on the European E46 M3. Lucky Europe. But you can have them, too, right here in the US of A. The design provides improved cooling and fatigue resistance compared to the solid non-ventilated brake rotors fitted on the US spec E46 M3.
Thanks to aluminum center hubs, they also shed a couple lbs of absolute weight per wheel - but the real reduction is in rotational weight on each axle.
