CeramicSpeed Shimano 9100/9150 Oversized Pulley Wheel System: Coated, Alloy Pulley, Carbon Cage, Black

The CeramicSpeed Oversized Pulley Wheel System provides optimization and increased efficiency of the rear derailleur through its extremely low-friction bearings and unique overall design.

• Features a 13-tooth upper pulley wheel and a 19-tooth lower pulley wheel to provide absolute optimization of the rear derailleur