The Zipp Service Course SL Stem, crafted from 7075 aluminum, features a shape that strong and lightweight, resulting in a 1.85 grams per newton meter of stiffness. That results in no-flex sprints and accelerations.Features-Forged AL-7075-Machined and relieved faceplate-Features titanium hardware with TORX heads on all bolts for precision torque readings and ease of adjustmentItem Specifications-Stem Angle (deg):+17-Stem Angle (deg):-17-S.H.I.S. Stem Clamp Diameter:28.6-Defined Color:Black-Stack Height:41-Weight:125-Color:Matte Black-Material:Aluminum-Length:90-Bar Clamp Diameter (mm):31.8