alpha Racing Rear Brake Disc 220 x 4.0mm EVO BWM S1000RR (OEM, Racing Wheels), magnesium or aluminium, in high-quality steel. Brake disc in high-quality steel to be used with BMW OEM wheels and racing wheels in magnesium or aluminium, slotted for optimized heat dissipation and good braking characteristics in wet conditions. Weight: 0.58 kg. Notes: To be used with standard sensor ring for ABS/DTC functionality.