Features: brand new and high quality The Stirling Engine is easy to operate and you just need to take it out from the box then fill the lamp with 95% alcohol to heat the glass cylinder; then, after warming up for seconds, give the flywheel a spin and it will rotate rapidly and smoothly. It will light up the color-changing LED bulb mounted on the little generator. Due to the heat of high-grade alcohol, the engine will run frantically and generate electricity. The power will pass through the wires and drive the LED lighting. This is really an interesting and imaginative toy. The engine model is made of high-quality metal and elegant craftsmanship, which is sturdy and durable. Through hands-on operation, you can observe the whole process of the Stirling engine, understand the working principle of the Stirling engine more intuitively, and deepen children's interest in physics. It has a wide range of applications, such as children's science projects, physics/mechanical learning, classroom demonstration props for teachers, friends, family members, parents, children's birthday gifts, etc. Specifications: Material: Metal Size: Approx. 16x8x8cm/6.29x3.14x3.14inch Package Includes: 1x Stirling Engine Motor Model note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.