Stirling Engine Model Adjustable Speed With Vertical Flywheel Physics Power Science Experiment Engine Toy Boys Gift Features: Novel Design: The design of this Stirling engine model is novel and unique, with a simple and exquisite shape, and a sophisticated wooden base, which shows more high-end taste. The top knob can adjust the amount of air conduction to control the speed of the Stirling engine, which is easy to observe the dynamics of the piston and bring more good look. High Quality: The main parts are made of aluminum alloy and brass, which are sturdy and durable. The heating cylinder is made of quartz glass with low expansion coefficient and high temperature resistance; fine workmanship, perfect details, and a combination of texture and beauty. Fuel: 95% alcohol (need to be prepared by yourself), pay attention to not add water, kerosene, gasoline, lighter oil, liquor, etc. Starting Method: Place the Stirling engine model on a horizontal table, add two-thirds of 95% alcohol to the alcohol lamp, ignite and heat for 30 seconds, then turn the flywheel, and the engine can run. Working Principle: The Stirling engine outputs power through a cycle of cooling, compression, heat absorption, and expansion of the air in the cylinder. Use Significance and Value: Through hands-on operation, you can observe the operation process of the entire engine, understand the working principle of the Stirling engine more intuitively, and deepen your interest in learning physics. Gift: Its superior quality and exquisite appearance also make it have a high collection value, can be used as a high-end desktop decoration, can also be used as exquisite gifts to give back to others. For Age: 14+ Due to different batches, there may be differences in the appearance, color, and printing of the product, which does not affect its use Color: As Shown Material: metal+wood Package Contents: 1 x Engine Model