Spin the disk and enjoy a hypnotic light display with ever-changing sound. The disk seems to spin forever, rotating and precessing as it slowly transforms gravitational potential energy into kinetic energy. The concave mirror base reflects the disk's spectacular effects. Amazing to use in a darkened room with a flashlight or laser. Includes magnetic holographic film for extra dazzle. 7.5 cm dia. disk, 20 cm dia. mirror.
