Grip & Seat: TPR (TPR grip is very suitable for children"s small hand. And most important is that our grip has passed the standard of EN71 and CPSIA. Which shows our grip is no heavy metal or poison that might hurt children. Fork & Frame: Composite Plastic (the fork and frame of Pop Bike use special gas to assist while injection molding, this made the plastic 30% stronger than normal plastic. And the cross area of fork and frame, we have special design to limit the angle when it"s turning, and make sure children won"t cut their hands while riding Tire: EVA