Shimano SM-BH59 Olive and Connecting InsertShimano BH-59 Hose Connecting Bolt Unit. This hardware is necessary for replacing hoses, or shortening the legnth of hose on pre-bled disc brakes. Cut the hose to length, insert the barb into the hose - slide threaded nut and olive onto hose. Once threaded to proper torque, the leak proof tight seal will be ensured.689228127036