The classic interchangeable spiro-tracks let you create your own unique pattern shapes, taking your designs to a whole new and super level! This 18x13x1.5 inch package contains two racks, three design pens, six spiro-track end caps, one spiro-track tri-hub, four shaped wheels, 18 wheels in different sizes, 16 curved spiro-tracks in different sizes, two rings, spiro-putty, eight straight spiro- tracks, one 24 page design guide and jumbo paper and two 25 page design pads. Recommended for ages 8 and up. Conforms to ASTM D 4236. Imported.