Shimano 105 Di2 RD-R7150 12-Speed Road Bike Rear Derailleur offers smooth and precise gear changes with its advanced Di2 technology. A simple touch is all it takes to shift gears, making your ride more enjoyable and efficient. Key Features The Shimano 105 Di2 RD-R7150 12-Speed Road Bike Rear Derailleur is the system's control centre, featuring wireless connectivity to the shifters. It also serves as the charging point and provides ANT+ connection to third-party devices, replacing the traditional handlebar junction. A button on the derailleur allows for Di2 operations, with an LED light indicating synchronised shift mode, setting mode, and charge status. Its sleek, low-profile Shadow design reduces the risk of damage in a crash. Automatic motion programming ensures quick, smooth, and effortless shifting at the touch of a switch. By replacing mechanical cables with electrical wires, the derailleur eliminates issues like contamination, corrosion, and stretching, ensuring seamless gear shifts. It includes a saver (fuse) function to protect the inner structure from strong impacts. Constructed with high-tolerance cold-forged aluminium link plates and body, it is both lightweight and durable. Four self-lubricating micro-machined fluorine-coated link pivot bushings provide low-friction shifting. Compatible with 12-speed E-tube Di2 systems. Supports a wide gear ratio, compatible up to 11-36T. This derailleur is designed to enhance your cycling experience with its innovative features and reliable performance.