Bosch QuietCast Premium Disc Brake Rotors utilize innovative materials that ensure the highest quality performance, prevent rust and corrosion with clear-look coating protection, provide a clean look for today"s open-wheeled vehicles, are 100% precision balanced for smooth operation, and have a factory-engraved edge with code and minimum thickness specifications. Professional installers recognize Bosch as OEM and can be assured Bosch QuietCast­ Premium Brake Rotors provide the highest quality to the aftermarket, from the company with over 70 years of OE braking expertise.