Feature: This Low Temperature Stiring Engine could be a great gift for your friends or families.  It is almost ready to run: after the installation, put it on a cup of hot water, then it will run itself.  Low Temperature Stirling Engine.    Description: Item Name: Stirling Engine;  Size: 102 X 102 X 125mm;  Material: Steel and Glass;  Speed: up to 180-250 RPM;  Start Temerature Difference: 20 ℃;  Weight: 250g;    Note: Can use pencil to lubricate all the connections,other oils are not recommended.    What is stirling engine?  A Stirling engine is a heat engine that operates by cyclic compression and expansion of air or other gas, the working fluid, at different temperature levels such that there is a net conversion of heat energy to mechanical work.The engine is like a steam engine in that all of the engine's heat flows in and out through the engine wall.    How does this amazing machine work?  all you need is hot air, cold air and compression, and this engine will run itself This low temperature stirling engine, it run on warm / cold surface, and it requires a small difference in temperatures to run. Very fantastic craftsmanship, made with Metal Alloy Being a Gift, or a Display on your desk or anywhere     Package Included: 1 x Low Temperature Stirling Engine