[Bicycle stem tube] This fork stem extender provides a stem height of up to 70 mm (2.75 inches) and is suitable for most fork tubes with 28.6 mm (1-1/8 inches) bike. [Adjustable height] This bicycle handlebar stem is equipped with 5 spacers (15mm + 410mm), so you can change the spacers to customize the height of the stem according to your riding needs. [Easy to install] Just use this bicycle handlebar extender to connect the original front fork rod, and tighten all the bolts with the included hex wrench. [Sturdy material] This front fork rod extender is made of 6061 aluminum alloy, which is 20% lighter than ordinary aluminum alloy rod extenders. Strong corrosion resistance, no rust, high toughness and no deformation. [Applicable bicycle] This bicycle head-up adapter is suitable for most road bicycles, mountain bicycles, track and field bicycles, MTB, BMX, DH, etc., suitable for modifying and upgrading your bicycle. Installation Steps: 1. Remove the cover of the original bicycle handlebar. 2. Remove the handlebar bracket. 3. Install the bicycle front fork rod extender, then adjust the position and fix the adjustment screw.. 4. Add some spacers according to the height. 5. Install the handlebar bracket and fix the screws on the bracket. 6. Install the cover of the bicycle front fork rod extender.