The shimano st rs505 hydraulic disc brake sti set great value sti levers for hydraulic disc brakes offer powerful braking and effortless 11 speed shifting the hydraulic brake lever provides powerful controllable and consistent stopping power with less effort especially from the hood position shimano st rs505 hydraulic disc brake sti set features vivid indexing provides a constant amount of shift lever force across all 11 sprockets ergonomic short shift arc follows natural hand moveme