Planet of Toys has an excellent friction-powered toy for both girls and boys. The dump truck set is a fantastic, safe, inventive, and lovable friction toy for kids aged 3 and up. Simply keep rolling with friction power. One garbage debris truck, one garbage truck car, and one tank truck car are available. Simply push the dump truck forward many times before releasing it and watching it roll! It is extremely popular among children.Friction truck toys are ideal for helping children develop hand-eye coordination.