This expansion pack includes over 25 components to extend the fun of your GraviTrax with even bases and levels to experiment with.Contents: 2 Base Plates, 1 Transparent Level, 8 Large Height Tiles, 4 Small Height Tiles, 2 Switches, 1 3-in-1 tile, 1 Vortex, 1 Finish Line, 4 Basic Tiles, inserts for basic tiles: 2 Catchers, 1 Freefall, 1 Splash, 1 LandingExperience the power of gravity! GraviTrax is the all new STEM track system from Ravensburger! Use your imagination to build superb tracks and set the gravity spheres rolling! This STEM system [Science, Technology, Engineering and Maths] is an ideal one to teach kids about gravity, magnetism, kinetic energy and fun. Hit a snag? Freestyle with your own track design or use the tasks and blueprints included to help you to get started in the world of GraviTrax! Are the gravity spheres stopping or flying off before reaching the end target? Time for some problem solving. Rebuild and try something different! The GraviTrax track system can be extended indefinitely with extra track packs and add-ons each sold separately.