Flashing LED Whirly Wheel Magnetic Retro Toy At least three times as much fun as it ought to be This magnetic gyroscope is festooned with multicolored LEDs that flash while it spins around a hand-held set of 2-1/2" dia wheelie tracks Spins as long as you keep giving it a little wiggle, and you can't beat that. Includes (3) button-cell batteries for the flashers.