Function: 1. Universal: Stirling engine model kit has a wide range of applications such as children's science projects, Christmas gifts, physical machine learning tools, classroom teacher demonstration props, etc. 2. Smooth operation: There are 4 anti-slip pads on the bottom of the scientific Stirling model, which ensure smoother operation with low noise, low pollution, and low operating costs. 3. Easy to use: Stirling scientific physical model is durable; fill the igniter with 95% alcohol and light it. Let the flame heat the cylinder at the rounded end for about 60 to 120 seconds, then gently push the wheel to start the engine. 4. High practicality: Stirling engine model is designed for physical experiments; glass tubes and glass alcohol lamp allow direct observation of piston movement. 5. Practical gift: The Stirling engine model is a well-designed mechanical toy that clearly demonstrates the basics of an external combustion engine and makes a great gift for family and friends. Specification: Item Type: Stirling Motor Model Engine Eonal Toy Material: Zinc alloy, stainless steel, glass, wood Color: Mirror, silver Product Size: Approx. 160x85x95mm / 6.3x3.3x3.7 inch (manual measurement error is about 1 cm) Output voltage: 3.0-5.0 V Fuel: 95% alcohol Package List: 1 x Stirling Engine Model Engine Eonal Toy 1 x Alcohol Cover 1 x User Manual 1 x Alcohol Dropper (3 ml) 1 x Spare Heated Glass Tube 1 x Lamp Bead 1 x Rope Note: - Manual measurement error is about 1 cm. - Read the instruction manual before use. - Check the tightness of the components and ensure no glass damage; the glass tube should be intact, and the large wheel should turn smoothly with good elasticity. - Light the alcohol lamp and warm the tube for about 20 seconds (very important), then turn the large wheel to start the engine.