SUPERFUN 101 FEATURES: Mechanical lap counter, powerbase integrated as combo track, and short circuit protection assure toys safety. Track length: 8'10". Layout: 3'8"x1'10". PRECISE SPEED CONTROL: Comfortable grip speed controllers provide full control over speed of each slot car to control course difficulty compared to most slot cars that have fixed speeds. SIMPLE USB POWER SYSTEM: An innovative application in the slot car toy industry. Convenient & safe. Plug the included USB into your own portable battery, your smart-phone USB power adapter or USB adapter outlet plug to play. HIGH QUALITY CARS: Detailed to-scale cars with bright LED headlights and strong magnetic base. Cars run smoothly and quietly because of high precision gear design and installation. WIDER TRACKS: The almost 9 foot mega track is wider & longer compared to traditional 1/43 scale slot racing tracks making the distance between the cars more comfortable. Buy 2 sets to expand track length for twice the fun!