This is the slot car set with a self-contained track that unfolds from its carrying case to form an instant, two-laned raceway. Requiring no electricity, two hand crank dynamos power both the included race cars as they careen around track in separate (but equally challenging) lanes with ramps, overpasses, and hairpin turns. The dynamos allow precise control over speed while racers slow down around curves and accelerate in straightaways--the faster the crank the faster each car goes. A built-in lap counter keeps racers aware of lap position automatically. The race cars are the same kind found in larger, more expansive sets, with responsive contact brushes and smooth-rolling foam rubber tires; includes spare tires and extra brushes. Ages 4 and up. Deployed 36" L x 17" W x 2" H; closed 18" L x 17" W x 4" H. (6 3/4 lbs.)