The speed change mountain car can be installed, Apply the horizontal diameter approximately 22 MM. Lock the sleeve + aluminum alloy ring. Material: Environmental rubber. Size: length 130mm. Weight: Approx 200g. Color: Black, White, Red. Package Included: 1 pair + aluminum alloy ring. Features: Easy to install, Ergonomic handle design groove, Greatly enhance the bicycle exterior texture, and make your car more valuable sense, also can increase the shock-absorbing effect, Environmental rubber material can be non-slip effect, greatly improving ride safety, Driving, spine angle can be adjusted to reduce the physical burden, Increase the efficiency of uphill riding, save the physical strength, increase the speed.