Easy to Operate: Just place it on a cup of hot water, and gently flip the wheel until the wheel can run automatically.Superior Performance: By operating the engine, children would observe and know the operational process and more intuitive understanding of the operating principle of Stirling engine, deepening interest in physics.A Classic Stirling Engine Model: Made of premium metal, and the high intensity PC material is heat-resistant and harmless. Transparent body gives you a clear view on how every parts work.Safe for Children: No need to fire an alcohol lamp, for children. Fully assembled, no need to install it yourself.Great Educational Toy: classroom or laboratory experimental teaching aids, the students, teachers, children, friends and colleagues.Net Weight:218g/7.7ozColour:GoldMaterial:Metal+PCSize:9.9 x 11.4cm()Package Contents:1 x Stirling Engine ModelOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.