Feature:1. The operation is simple, the hot water is preheated for 1 minute, and it can be started by turning the flywheel clockwise.2. Made of high-quality materials, exquisite and beautiful, the modle is the perfect combination of texture and beauty3. The model kit has a wide range of applications, gifts for children's science projects, physicsmechanical learning, ect.4. Convenient for handson operation, more intuitively grasp its working principle, and deepen your interest in physics.5. The product itself has been assembled, has collection value, can be used as decoration, can be directly used in experiments, simple and convenient.Specification:Item Type: Stirling Engine ModelMaterial: Zinc AlloyFunction: Can Reduce the Temperature of the Cup WaterSize: 11 x 9.5 x 9.5cm/4.3 x 3.7 x 3.7in (manual Measurement, There May Be Slight Errors).Package List:1 x Low Temperature Stirling EngineNote:Please allow 02 cm error due to manual measurement. Thanks for your understanding.