Hidden Magnet in One Face Dice - Full set (6 Dice 1-6 rollers)A powerful neodymium magnet is hidden 1mm below the surface of one face of the die. The roll of the die can be affected by a second magnet, either to attract or repel. It can be controlled through a thickness of at least 20mm (4 5 inches) of wood. Commonly used in conjunction with a magnetic finger ring, a magnet strapped to the operators knee pressed against the underside of a table, or an electromagnet built into the rolling surface. The rolling