This Mountain Bike Stem is constructed from aluminum alloy ensuring it is incredibly durable,lightweight and strong. you can up or down the heigth of your handlebar,perfect angle,It helps to relieve the pressure of your shoulder and back, and bring you enjoyable and relaxed cycling experience. just connect up the original front fork stem. Four bolt bar clamp holds bar securely in position. This bike stem suitable for most mountain bikes, road bike, fixed gear bicycle, BMX, MTB, bike etc. If you have any questions regarding the product or service, please feel free to contact us, we are always at your service.