Shimano GRX 815 Di2 2x11sp Rear DerailleurThis top-quality rear mech is specifically designed for riding on rough roads, gravel and mud as it gives you smooth shifting performance. Highly versatile, this stunning model's chain stabiliser prevents chain slapping and drops as you conquer every road. You'll notice its silent and uninterrupted rear shifting on especially harsh terrains, where other rear mechs could struggle. What's also very impressive is its switch stabiliser which provides you with the freedom to turn it on/off to match the terrain conditions.Smooth Shifting Rear MechFeaturing the revolutionary Di2 shifting system, this rear mech delivers instant, accurate, lightning-fast shifts on every run. At the push of a button, you can maintain precise control even in the most extreme conditions with its electronic brain keeping you in charge. Additionally, you can change gear even under heavy load while climbing or accelerating making it perfect for tough rides. Smooth and reliable on mixed surfaces, its gravel-tuned clutch tension is ready to conquer all the challenges of a long ride out. Whether you're riding after work with your buddies or exploring new and unpredictable surroundings, this 2x11 speed version won't let you down.Features:  Use: Gravel, Road  Link Bushings: 4 fluoric coated link bushings   Speed: 11 speed  Spring Type: Shadow RD+ Low Sprocket Max: 34T  Low Sprocket Min: 30T  Top Sprocket Max: 11T  Top Sprocket Min: 11T  Max Front Difference: 17T  Total Capacity: 38TTechnologies:  Digital Integrated Intelligence: The revolutionary DI2 shifting system solves the challenges drivetrains present to the power-delivery equation in cycling. DI2 gives you instant, accurate, lighting-fast shifts the first and every time, at the push of a button. Even in the most extreme conditions, shifting is precise and controlled. You can change gear even under heavy load while climbing or accelerating. With DI2, you are in complete control.  E-Tube:  The E-Tube platform's “Plug & play” and D-FLY wireless connections make it easier than ever to check the system's status, and apply customized settings to DI2 and Shimano Steps components with a PC, tablet or smart phone.  Shimano Electronic Intelligent System: The SEIS innovative shift technology is still based on the Shimano Index System that has proved its superior gear changing characteristics over the years. The big difference is that in this case, the shifting action is provided for by electronics instead of mechanics. A 2-year warranty is offered with all Shimano products from Chain Reaction Cycles (3 years on Dura-Ace and XTR products).Buy Shimano Components from Chain Reaction Cycles, the World's Largest Online Bike Store.