The SHIMANO GRX RD-RX815 Di2 rear derailleur combines gravel-ready performance with electronic precision. Its integrated chain stabilizer reduces noise and enhances shift security across mixed terrain, with an easy-to-toggle switch for road-specific riding. The Di2 electronic system delivers accurate, synchronized shifting across 11 speeds, while supporting road cassettes up to 34T low sprocket. Purpose-built for adventure cyclists demanding reliable shifting in demanding conditions.