Shimano Steps RT-EM810 Disc Brake Rotor – 203mm Center Lock External Lockring Rear Only with Magnet Bracket. Shimano RT-EM810 disc brake rotors for speed sensor systems deliver powerful and consistent brake performance in all riding conditions. The ICE TECHNOLOGIES FREEZA rotor significantly reduces heat build-up in the brake system to ensure consistent high performance braking even on the steepest downhill stretches.

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