We're pretty excited about Hayes' new Dominion brake and the new D-Series Brake Rotor is engineered exclusively to work with it. Available in 180 and 203mm diameters, Hayes' goal with the rotor was to better manage heat and reduce noise. By using a 1. 95mm thick rotor it's better able to absorb heat under braking and dissipate it keeping your stopping more consistent. The other engineering feat is called Modal Resonance Cancelation or MRC which goes about reducing the harmonic noise associated with most rotors. Hayes used FEA-optimized shapes to oppose the compounds used in the Dominion pads to cancel out vibration so the brakes are less likely to vibrate leading to better brake feel and less noise. Finally, Hayes employs its QuickBite2 technology to provide a quick, consistent burnish while breaking them in so you get predictable braking over the life of the rotors with no dreaded turkey gobble.