Send the marble in the reverse direction with the flip! As the marble rolls into the flip, it releases and transports up a level, slinging it in the opposite direction. This accessory also includes 6 additional tracks and must be combined with the gravitrax starter set. Gravitrax is a modular, electronic-free interactive track system where you can design and build your own marble runs. This STEM toy for boys and girls 8 and up, encourages experimenting with gravity, magnetism, and kinetics to propel your marble to the finish. Designed with open play in mind, the concept offers endless possibilities to design a different track every time you play. Expand your builds and add some action with a variety of expansion sets and Accessories.