This little robot is tough. Run by a single motor, he walks with a decidedly " angry" pace -- and if he falls over, he picks himself up again. An awesome design with an amazing gear mechanism, he will not quit. Over 50,000 sold in Japan and a big hit at the International Robot Exhibition. Easy to build.• Easy to build in less than 1 hour• Complex motions from a single motor• 3 modes: Fall and get up mode, dance mode, and somersault mode• High impact plastic• Requires 2 AA batteries (not included)• For ages 8 and up