Stainless steel Mini Hot Air Stirling Engine.
Very interesting item. Once added fuel (alcohol) and fired up, it starts to move until the fuel ends. I have chosen this particular model because it has a motor/generator coupled, I wanted to show the conversion of mechanical movement into electricity, firing up a led. Unfortunately the generated voltage (0.28V) was to low and seller was not able to support me. In all the cases is is a nice item for conversation.