Tweak, tinker, and experiment to make your balloon-powered craft go as fast as can be. Our book contains super-clear building instructions, scientific principles, and real-world examples that make rocketry and jet propulsion simple. Air Power brings a breath ? make that a blast ? of fresh air to Sir Isaac Newton?s famous Laws of Motion. It turns out that rocket science is way too much fun to leave to the rocket scientists. Comes with: 48 page instruction book, 4 plastic parts (2 mouthpieces, thrust vent for hovercraft, blast cap), straws for blast pipes, 8 wheels, 4 axles, one hot-rod body, one hovercraft body, rocket fins and tube, helicopter blade assembly, three 9" balloons, two 6" balloons. Note: balloons contain Latex.