The Shimano Ultegra Di2 RD-R8150 rear derailleur delivers Shimano’s fastest and most accurate shifting for modern road riding. Designed for 2x12-speed drivetrains, it brings race-level electronic performance to riders who demand smooth and consistent gear changes. This is Ultegra refined for today’s roads. Lightning-Fast Di2 Shifting: Integrated with Shimano’s latest Di2 platform, the RD-R8150 executes gear changes instantly and precisely. Shifts are crisp and dependable under load, whether sprinting or climbing. The electronic system ensures accuracy ride after ride. Single Cage, Wide Compatibility: A single cage length supports a wide range of cassette options, handling low sprockets from 28T to 34T. This versatility allows riders to choose gearing based on terrain without changing derailleur setups. Ideal for varied road conditions and endurance riding. Optimised for 12-Speed Road Drivetrains: Designed specifically for Shimano’s 12-speed road groupsets, the RD-R8150 ensures smooth gear transitions across the entire cassette. Chain control and alignment are tuned for efficiency and quiet operation. The result is seamless performance at speed. Fewer external components improve reliability and aesthetics. The Ultegra Di2 RD-R8150 is built for riders who value speed, precision and modern electronic control.