Shimano Dura Ace 7900 10 Speed Rear Derailleur- with lightweight carbon cage & wide link design gives quick accurate shifts, & unmatched drivetrain efficiency- Full carbon fibre inner & outer pulley plates enhance rigidity & significantly reduce weight- High tolerance cold forged aluminium link plates & body construction provide for extremely light weight, strength & durability- High rigidity wide outer link plates the pulley body to increase pivot joint rigidity- Sealed pulley bearings reduce friction & rotate silky smooth increasing efficiently- Four self-lubricating micro-machined fluorine-coated link pivot bushings provide low-friction shifting- Pulleys are made from tough Du Pont Zytel for longer life & less chain noise- With a total capacity of 33 tooth, it is able to operate with wide gear ratios up to a 28 tooth cassette sprocket- Hard wearing Dura-Ace finish & graphics for long lasting good looks- 10-speed compatible- Weight: 166 grams