31.8 mm

【Durable road bike stem】Material: Carbon Fiber + Aluminum Alloy; Appearance: 3K Glossy/3K Matte; Weight: Approx. 120~170g; The bicycle stem is made of aluminum alloy and carbon fiber. It has passed the long-term strength test and is guaranteed to be durable and long-term; fork diameter: 28.6 mm (1-1/8"), handlebar diameter: 31.8mm, angle: 6 degrees. 【Multiple sizes available】MTB stem length: 60/70/80/90/100/110/120mm, 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】bicycle stem of different lengths: stem length90mm, better stability, more suitable for high-speed riding. 【Easy to Install】Connect the original bicycle fork, the four-screw rod clamp holds the rod firmly in position. Install the product correctly. Please follow the specified tightening torque (4Nm). Recommend using a hex wrench to tighten the screw. 【Installation Tips】When assembling, please confirm that the handlebar diameter is 31.8mm. The center width needs to be confirmed to properly lock the product and install it manually with a hex wrench; make sure the diameter of the front fork is that of the stem corresponds and that the size for; when installing, you can also apply carbon fiber mounting paste to the bicycle handlebar to ensure a tight fit.