Play in the big leagues with the “GraviTrax PRO Giant Starter-Set” and create the tricked-out marble run of your dreams! Elevate your imagination to new heights with the “GraviTrax PRO Giant Starter-Set”! With 409 diverse pieces, this massive construction set offers everything you need to build giant vertical action-packed marble runs! Connect walls, pillars and balconies to form structures with suspended stunts and intricate pathways. Included plans make set up a snap while encouraging creativity and independent play. Explore endless possibilities to experience the power of gravity and educational fun today! GraviTrax is the STEM-friendly, expandable construction set kids love! 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.