Problem Solvers Under Stem Mount - Shimano Di2, 17 degree - The Under Stem Mount allows riders to secure a Shimano Di2 Junction Box to their bike quickly and easily without the need for zip ties, duct tape, or other unreliable attachments.95mm length, 44mm width, 6mm heightCompatible only with Shimano Di2 Junction BoxLightweight alloy headset spacer with nylon body (9g)