8 years & up. Experience the power of gravity with Gravitrax! Increase the action by increasing the height of your run with the Gravitrax Building Expansion. With over 25 additional elements, expand your Gravitrax Starter Set vertically combining height tiles, base plates, freefalls, switches, and even another level. Test yourself to see how high you can build your track before reaching the finish. Gravitrax Starter Set not included.