Bicycle MTB And BMX Stem manufacturers The bike stem is sturdy, constructed of high-strength aluminum alloy. Easy to install, just connect up the original front fork. Four bolt bar clamp holds handlebar securely. Depending on the thickness of your handlebar, you may need to install a shim. the pain caused by the original setup in shoulders/arms/back had to be corrected. This stem and a riser handlebar did the trick, allow you to sit more upright on bike which is better for your backBicycle MTB And BMX Stem manufacturers website:http://www.lj-bicycle.com/bicycle-accessories/bicycle-mtb-and-bmx-stem/