Hape Roller DerbyDiscover the joy of guiding objects along the tracks (fast, slow, backwards and forwards). As your child gets older, tell them how gravitational energy turns into momentum. Inspire them to explore by themselves. Each side has different tracks, doubling the fun. The bell on the bottom rings when the ball reaches the end of the track. Suitable for 12M and above Colorful wooden balls, peek a boo holes and fast tracks create a dual sided mountain of fun