Give Kullerbü track systems a boost with the High Altitude Expansion Set, designed to raise the excitement (and the balls!) to new heights. This 10-piece set of risers lets young builders increase the elevation of their tracks in safe, stable increments, adding complexity and thrill to every race and curve. Perfect for little engineers looking to expand their world of motion, this set enhances creativity and supports early STEM learning, all while keeping play dynamic and endlessly customizable. • Build Upward, Play Longer: Adds height and variety to Kullerbü marble runs for more action-packed fun. • Precise and Easy Elevation: Designed to raise track sections in consistent, stackable increments for smooth transitions and stable builds. • Perfect Add-On for Kullerbü Fans: Fully compatible with all Kullerbü tracks, ramps, and elements. • Durable and Child-Friendly: Made from high-quality, kid-safe materials built to withstand active play. • Encourages Creative STEM Play : Boosts spatial reasoning, cause and effect understanding, and early engineering thinking.