RT-EM600 E-bike rotors with built-in speed sensor magnet provide consistent braking performance through energy control. Key Features Rotor houses the magnet necessary for speed sensor function on Shimano STEPS equipped E-bikes allowing frame clearance for wider tyres Compatible with E8000 / E7000 / E6000 / E5000 systems and for rear wheel use only Rotors are durable, lightweight and rigid, using the proven Shimano Centre-Lock system giving increased strength and security with an easy set-up Precision cut and drilled braking surface improves pad clearing in muddy conditions while aiding cooling under high load Large alloy spider is a highly rigid and lightweight support for the rotor surface Super polished braking surface gives excellent braking performance