Shimano specs BH90 brake hose with all of their better brakesets, like XTR, XT and SLX. The BH-59 is for road/gravel/cross hydraulic. If you trim down your housing of re-bleed your system, you will need to replace the Olive and Connecting Insert (also know as a Barb). We sell these as a two piece kit and is all you need to re-attach one hose. Purchase two if you are going to service both front and rear brakes.