Expansion for the marble run system. Recommended for ages 8 and up. Number of pieces: 14. Made of plastic. Includes many exciting components to expand the marble run. Playable only with the GraviTrax Starter Set. Includes instructions. The Extension Bridges adds more possibilities and fun to the GraviTrax track. When combined with any GraviTrax Starter Set, the Extension Bridges offers even more options and marble fun in the GraviTrax universe. How much longer can the marble roll with the new elements? Ravensburger has been a staple in children's rooms in Germany and around the world for decades and is the leading provider of puzzles, games, and activity products in Europe, as well as children's and youth books in the German-speaking area. 85% of the products are manufactured in Europe and are sold worldwide from there. The Ravensburger publishing house was founded in 1883. A year later, in 1884, the Ravensburger game publishing house was established. It celebrated its first milestone with the best-selling game "memory." Since 2009, the company has also focused on new technologies with the founding of its subsidiary Ravensburger Digital GmbH. It combines the classic gaming world with intelligent electronics, enabling interactive learning.