Feature: 1. It is very suitable for those who are passionate about science or demonstrating the laws of physics in the science classroom. 2. This perpetual device can be a perfect gift for your friends or family, or it can be an exquisite home decoration craft. 3. After installing the battery (not included), and then gently shake it with your fingers, the device will start to rotate. 4. The simple and modern style is full of fun, and the electronic swing device is also a dynamic art on your table. 5. High‑quality materials, made of ABS and zinc alloy, strong and durable, safe and smooth to touch. Specification: Item Type: Perpetual Motion Toy Material: ABS + Zinc Alloy Color: As shown in the picture Product Size: Approx. 16x19x11cm / 6.3x7.5x4.3in Weight: Approx.300g/10.6oz Battery: 4 x AA battery(Not included) Application: Home decoration, festival gifts, etc . Package List: 1 x Base(Battery Not Included)2 x Supporting Arm1 x Swinging Rack Note: 1. Please allow 1‑2in error due to manual measurement. Thanks for your understanding.2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard.