1Aluminum Material: Made of aluminum alloy mateiral with CNC machining, corrosion resistance, strong for heavy duty work. 2Surface Treatment: Anodic oxidation treatment, no rust or oxidation with smooth surface, more gorgeous, bright and lasting color. 3Full Hollow Design: Has large area hollow but the strength is not reduced, matching 6 dazzling, suitable for 4mm inner hex wrench. 4Firm Lock: Bilaterally firm lock, more stable without deviation, will not fall off when you doing difficult movements. 50 Angle: 0 angle short bike stem is more flexible to use, easier to achieve difficult performance. Item Type: Bike Stem Material: 6061 Aluminum Alloy Application: For Mountain Bike Product Size: Handlebar Diameter: Approx.31.8mm/1.3in Steering Riser Front Fork Diameter: Approx.28.6mm/1.1in Holes Center Distance: Approx.35mm/1.4in Installation Depth: Approx.40mm/1.6in Weight: Approx.117g/4.1oz Angle: 0 1 x BikeStem1. The height of this bike stem is 40mm/1.6in. The original handle requires front fork gasket jwhen the height is more than 40mm/1.6in.2. Locking the bike stem cover needs to tight diagonal 2 screws together. Do not lock one screw of a side or only lock a side.3. After the bike stem installed, it needs to be about 5mm/0.2in higher than the front fork to lock. If it is not high enough, add washers under the bike stem.