The Clock - Koontz Build a Clock and Discover How the Hands Move Did you know in a mechanical clock, the motion of the hands depends on the motion of the gears? Discover the secret to the clock’s hand movements with this Koontz Clock kit. This 21 piece kit assembles easily without tools. Simple step-by-step instructions and activity book included. Part of the Koontz series of assembly kits for kids. Assembled model is made of recycled cardboard and measures 10" x 16" x 6" . For ages 8+.