? Made of high quality butyl rubber, Have good flexibility and excellent cushioning ability, ? It There is also demonstrates tear resistance, Wear resistance, Heat resistance, resistance to aging. ? When you ride on rough roads, you can avoid violent shaking of your hands and feet to protect the safety of you and your family, especially your children. ? Please check the position of the valve, and make sure you install them in the right direction. ? If you encounter any problems, Please contact us by email immediately, We will help you solve the problem within 24 hours.