With over 100 pieces and 18 different construction elements, the GraviTrax Starter Set offers everything you need to begin building your own action-packed track systems. Discover how the laws of physics affect the journey your marble takes with curves, junctions, freefalls and even a cannon. Experiment using different heights and angles to control the speed of the marble to get it to the finish. For ages 8 and up. WARNING: CHOKING HAZARD - Small Parts. Not for children under 3yrs. CHOKING HAZARD -- Toy contains a marble. Not for children under 3 yrs.