Abong Magnetic Wooden Cannon - Four-Stage Chain Reaction Magnetic Accelerator - Includes Rare-Earth Magnets and Ball Bearings CHAIN MAGNETIC ACCELERATOR - The Magnetic Cannon is a four-stage magnetic accelerator. It includes rare-earth magnets, steel ball bearings, and an 8.5-inch long firing trough IDEAL CENTERPIECE - This kit is a perfect centerpiece for science projects on kinetic energy and magnetism. BUILT FROM HIGH-QUALITY MATERIALS - Quality Canadian lumber is used in the making of the Magnetic Cannon. There is no lead used to ensure the safety of those who will use it. COMES WITH AN INSTRUCTION GUIDE - The package includes a well-detailed instruction guide to help you how to use the magnetic cannon. WOODEN KIT FOR ALL AGES - This kit is recommended for kids ages 10 and above. Even adults are sure to have with this Magnetic Cannon.