Introducing the Shimano GRX SM-RT64-M Disc Brake Rotor with External Lockring your ultimate replacement rotor for unparalleled braking performance. Upgrade your braking prowess with the Shimano GRX SM-RT64-M Disc Brake Rotor with External Lockring. Whether you ride on rough trails or tackle smooth tarmac, this rotor's cutting-edge design ensures reliable stopping power and precision control. Experience the confidence to take on any adventure choose the GRX SM-RT64-M Disc Brake Rotor and unleash the full potential of your cycling performance. | Shimano SM RT64 M Disc Brake Rotor with External Lockring 180 mm