Dimensions: Diameter 6 cm, height 9 cmBattery: Built-in three sections on the 7th battery (replaceable battery runs out)Methods: gyro connected transmitters, according to the strength and feel, clockwise 2-3, and then click over the ground, hit the gyro on the ground, it will rapidly rotating, and emits light colorful, and beautiful music around the gyro surrounded by a red laser circle, very beautiful (generally sliding tens of seconds).Principle: gyroscope or spinning top is a toy, called Chien. It can be about a central axis of rotation, the tip of the point balance in the gyro.