Joysway Super 254 USB Power Slot Car Racing set comes with a USB power system. It is the first and most innovative application in slot car toys industry. Traditional slot racing set is powered by batteries or transformer. With Joysway slot racing set, you can use the supplied USB power cable to connect your own power bank or smart-phone USB power adapter. Joysway USB power slot racing set is user-friendly.Details:Layout size: 6.1ft. x 3.7ft.Track length: 17.5ft.Output:5V2A, Input:5V2APlasticAssembly requiredFor ages 8 and up