The Rattleback is a long, thin, half-elliptical shape formed in plastic. It has a slightly offset center of gravity, which causes the Rattleback to spin in a directional rotation of choice, usually counterclockwise. If you attempt to spin the Rattleback in the clockwise direction, strong preference will cause the Rattleback to “rattle” back and forth after few rotations, stopping and then reversing the rotation back to the preferred counterclockwise direction. The directional preference is so strong that if the Rattleback is at a standstill and you push down on 1 end, it will begin turning.
• Comes with a Teacher’s Guide
• Assorted colors