Product details:

Young thinkers can design unbelievable ball track structures via simple, stacking planks. No glue, no connectors-just loads of constructive fun the 200-plank set includes enough components to create ramps, funnels, chutes and crazy contraptions like the black hole and bounce plate. Two balls and an 18-page idea book are included. The 50-plank set helps kids get things rolling with two balls and an instruction book detailing how to build a shooting gallery, turbine, step curve and more. Both keva contraptions sets are fully compatible.