The Eisco Floating Ring Magnet Set demonstrates magnetic repulsion and the principles of magnetic poles in a memorable visual way. Five ceramic ring magnets (32mm external diameter / approx. 1.3" diameter) stack on a vertical wooden dowel — when oriented with like poles facing each other, the magnets float above one another, dramatically illustrating that like poles repel. The wooden base measures 5.9" x 4" x 4" with a 150mm tall dowel. Note: keep magnets away from electronic equipment, magnetic media, and credit cards, and avoid striking them against hard surfaces to preserve magnetization.