Walking bike with pedeal. Frame&Fork: Steel. Thickness: 1. 2mm. Handle-bar: Steel. Saddle: PU Comfortable. Seat post: Steel. Wheel: Plastic. Tire: 12"x2. 125 or EVA Attachement part: Chain cover: plastic. Chain: KMC. B. B Part: Steel. Pedal: Plastic. Its Attachement bike part, when baby want to use it to ride, then parents assemble it. Baby can ride like 12" child bike.