The 4 boxes are made of GraviTrax height blocks in a cool design and in the colors green, gray and white. 2 of the boxes each contain 6 marbles, for a total of 12 marbles (6 silver, 2 red, 2 green and 2 blue). The other two boxes function as ideal storage options for other balls. The boxes can be stacked. From 8 years.
