The D-Series rotor was developed in conjunction with the new Dominion A4 disc brake, designed to provide consistent and reliable stopping power under all conditions. Proprietary friction surface, optimized for use with Hayes T106 (Semi-Met) or T100 (Sintered) pads to deliver fast, consistent burnish, predictable friction rate, and consistency across temperature and speed conditions MRC (Modal Resonance Cancellation): Tuned to cancel resonance and vibration, particularly when paired with Hayes T106 (Semi-Met) and T100 (Sintered) pads QuickBite provides the shortest path to high performance through a fast and consistent burnish 1.95mm thickness enhances heat dissipation Includes mounting hardware Use a Hayes Brake Adapter when changing rotor size If your new rotors are a different size than the ones you&';re replacing, then you&';ll need new brake adapters! Check out our guide to getting the right brake adapters to spend less time on the computer and more on the trails.