Shimano Ultegra Di2 RD-R8150 12 Speed E-tube Rear Derailleur

- Ultegra Shadow design with Di2 technology, shifting is easy and precise - just a light touch, as soft as a mouse click, is sufficient for the front or rear derailleur to instantaneously select the correct gear
- The rear derailleur is now the brains of the system with wireless connectivity to the shifters. It acts as the point the system is charged, provides ANT+ connection to 3rd party devises and replaces the handlebar junction
- Button on the derailleur for Di2 operations, and LED light denotes synchronized shift mode, setting mode and charge requirements
- Sleek appearance with Low profile Shadow design construction reduces risk of damage in a crash
- Programmed automatic motion at the touch of a switch makes this derailleur quick, smooth and effortless to shift
- The removal of traditional mechanical cables in favour of electrical wires not only eliminates poor shifting caused by contaminates, corrosion and stretching, but provides effortless gear shifts
- Derailleur contains a saver (fuse) function, where the inner structure is protected from strong impacts
- High tolerance cold forged aluminium link plates and body construction is extremely light and durable
- Four self-lubricating micro-machined fluorine-coated link pivot bushings provide low-friction shifting
- 12-speed E-tube Di2 compatible
- Wide gear ratio compatible with 11-28T up to 11-34T