Extend your marble run for even more amazing fun with the GraviTrax Trax Expansion set!Keep the fun rolling and add some height, distance and curves to your marvelous marble run with the GraviTrax Trax Expansion set! Designed with open play in mind, GraviTrax offers endless possibilities to design a different track every time you play. This Trax Expansion set adds over 40 components (tracks, height tiles, curves, intersection, marbles) to any GraviTrax Starter-Set to take your building skills to a whole new level! Experience the power of gravity and educational fun today!What makes a great toy? GraviTrax checks all the boxes! Its a creative, modular, expandable track system that challenges children to use their imagination to build their own marble runs! Electronic-free, GraviTrax construction sets use STEM-friendly concepts while building critical thinking and problem-solving skills. Completely open-ended, every GraviTrax set has a boredom-busting variety of play options for hours of fascinating fun. Once the basics are mastered, simply add expansion sets and accessories to propel those metal marbles around the tricked-out track of your dreams!Includes 6 large height tiles, 8 small height tiles, 7 curved tiles, 1 X-intersection tile, 6 tracks (1 long, 2 medium and 3 short) and 6 marbles (3 colored, 3 silver).Lasting durability for girls and boys ages 8 and up, its the learning toy children (and savvy adults) return to over and over again!