GraviTrax is an interactive ball track system from Ravensburger that allows boys and girls from 8 years of age to experience the laws of gravity in a playful way With the three action stones Gauss cannon, looping and hammer, and a total of 226 parts, both simple and demanding courses can be built, which makes the starter set XXL an ideal introduction to the world of the innovative marble run dimensions 34.29 x 34.29 x 17.78 cm From 8 years old