SHIMANO Rear Mech Dura Ace 9000 11spd SS

Improved operation gives more uniform shifting throughout the range. High tolerance cold forged aluminium link plates and body construction provide for extremely light weight, strength and durability. High rigidity wide outer link plates and pulley body to increase pivot joint rigidity. Sealed pulley bearings reduce friction and rotate silky smooth, increasing efficiently. Four self-lubricating micro-machined fluorine-coated link pivot bushings provide low-friction shifting.