[138 mm bicycle handlebar stem] This fork stem extender provides a stem height of up to 90 mm (3.54 inches) and is suitable for most forks with 28.6 mm (1-1/8 inches) Tube bike. [Adjustable height] This bicycle handlebar stem has 5 spacers (10 mm high), so you can change the spacers to customize the height of the stem according to your riding needs. [Easy installation] 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 bicycles, MTB, BMX, DH, etc., and is suitable for retrofitting and upgrading your bicycle. Product Use this bike stem lifter to increase the height of the bike stem, and change the spacer to customize the height according to your riding needs The stem extender is suitable for most bicycles with 28.6 mm thread and without steering tube. Height adjustable The handlebar adapter is equipped with 5 spacers (15mm and 410mm), and the height can be adjusted to 70mm by replacing the spacers. Made of aluminum alloy High-quality aluminum alloy, strong structure, durable and long service life. Fork rod extender Installation steps: Remove the cover of the original bike handle Remove the handlebar bracket Install the bicycle front fork rod extender, then adjust the position and fix the adjustment screw. Add some spacers according to the height Install the handlebar bracket and fix the screws on the bracket. Finally, install the cover of the bicycle front fork rod extender. Delivery: 1 x Bicycle handlebar riser 1 x hex socket screw