Smart balance wheel, also known as self-balancing scooter,electric skateboard, skywalker board, hoverboard, airwheel, is the most popular outdoor entertaining and vehicle tool in 2016. This mini size 4.5 inch smart balance wheel is designed for kids under 12 and we offer 4 color options. The tire size is 4.5 inch, it is safe for small kids to play with it!The unit comes with a UL/CE Certified Charger.