Aluminum

【Durable carbon handlebar stem】 Material: carbon fiber + aluminum alloy (the cap is a high-quality aluminum alloy); Appearance:3K glossy/3K matte/UD matte; Weight: approx. 120~180g; fork diameter: 28.6 mm (1-1/8"), handlebar diameter: 31.8 mm, angle: 6/17°. 【Several sizes available】road bike stem carbon length: 70/80/90/100/110/120/130mm, according to your own body shape characteristics, riding habits and matching to your own bike. Choose the right stem size, reduce pain in hands and Wrists.Reduce back strain. 【Advantages of different lengths】MTB stem carbon of different lengths: stem length 90mm, better stability, more suitable for high-speed riding. 【Easy to install carbon bicycle stem】 Connect the original bicycle fork, the four-screw rod clamp holds the rod firmly in position. Install the carbon road bike stem correctly. Please follow the specified tightening torque (4Nm); recommend using a hex wrench to tighten the screw. 【MTB stem installation tips】When assembling, please confirm that the handlebar diameter is 31.8mm. The center width needs to be confirmed in order to properly lock the product and install it manually with a hex wrench; make sure that the diameter of the front fork corresponds to the of the stem and that the size for; when installing, you can also apply carbon fiber mounting paste to the bike handlebar to ensure a tight fit.