Grimm's | Small Rainbow BallsGrimms wooden balls in rainbow colours is a set of 12 solid wooden balls. These small coloured wooden balls are the perfect size for a variety of marble runs. They bridge the gap between Grimms large wooden balls and Grimms small wooden marbles. Combined with the Grimms sorting boards, they are a wonderful 3 D matching puzzle and sorting game for children fro 3 years upwards. Combine with Grimms Building Rings as a balance game. Materials: maple wood,