3t pro alloy mtb stemmtb stemis a new design by 3t tailored expressly for the big hits of mountain biking of every discipline from cx racing to enduro wider stem clamp and squared off stem body confer exceptional resistance to torsional and bending loads four sizes 55mm100mm and 10 angle fit most riders torx bolts in titanium for security and robustness mtb stem prois built in al alloy finished shot peened and black anodized and weighs 120g 55mm size features weight 120g 55mm