Innovative: Design your own vertical marble runs with this specially designed system of flexible tracks that does not require any support structures, allowing you to build higher with fewer pieces. Intuitive & Mess-free: Tracks attach to smooth surfaces with the help of clever nano-adhesive pads that create a strong but temporary bond; the pads are not glue-based and can be quickly and easily repositioned without leaving behind damage or sticky residue. Open-ended & Educational: Combine different configurations and environments for endless possibilities; develop engineering and problem-solving skills and see physics in action. Tracks are made from renewable raw materials. What’s Included: The Loop Expansion Pack comes with over a dozen pieces to complement the Gecko Run Starter Set, including a loop stunt; additional marbles and nano-adhesive pads; 2 extra tracks; and more.