The Shimano GRX ST-RX815-R is a right-side Di2 hydraulic brake/shifter combo designed for gravel bikes. It combines an 11-speed electronic shifter with a hydraulic disc brake lever. This part is intended for riders building or upgrading a gravel bike with Shimano GRX Di2 11-speed components, particularly those using a 2x drivetrain setup. It is compatible with Shimano GRX RX815 Di2 groupsets and 11-speed Di2 drivetrains. The shifter works with GRX RX815 front and rear derailleurs and 11-speed cassettes.