Physical Science DIY Kits - StirlingEngine Model External Combustion Engine Model with LED lights Made of Galvanized aluminum, durable, high temperature resistance and low temperature resistance Theory - Similar to external combustion engine (EC engine): the burning alcohol lamp provides heat power to make the expansion of gas inside, then the gas molecular internal power increasing and working strongly to the flywheel. With the help of the flywheels, heat energy will convert into mechanical work, then into electrical energy Colorful LED lights directly demonstrate the process of converting thermal energy into electrical energy Great Educational Toy - Classroom or laboratory experimental teaching aids, cultivate children'sinterest in physics, more intuitive and easy to understand A stirling engine is a heat engine that operated by cyclic compression and expansion of air or other gas (the working fluid) at different temperatures, such that there will be a net conversion of heat energy to mechanical work. Specification: Material: Metal, Plastic and Glass Color: Silver Temperature range:-30~700 Assembled Size(LxWH): Approx. 18 x 9 x 14 cm / 7.09 x 3.54 x 5.51 inch Package Includes: 1 Set Stirling Engine Model with Colorful LED Lights