FANTASTIC SMART THING WITH EXTREMELY WELL MADE WHICH RUNS LIKE A DREAM----The stirling engine is produced with high quality material and elegant workcraft. this stirling engine adopts mirror surface stainless steel for the base, glass cylinder liner, zinc alloy flywheel. All the parts have done surface treatment to avoid rusting. Oil-free. OPERATION EASILY----Pour a cup of hot coffee, put the stirling on the cup, it run magically. When it slows down, the coffee temperature is suitable for drink. Enjoy physical powertrain mechanism display and coffee. It also can work on top of ice cube. Some guys put the stirling on cup of hot water and put small ice cubes on the stirling upper plate. This makes the temperature difference much bigger than normal, then it runs even more fast and crazy. Just enjoy the toy! LONG LASTING----It can run for 24+ hours continuous without any broken if there are continuous power supplies. One customer put the stirling on USB hot plate (excluded in the package) and the stirling runs on his desk for weeks. Don’t burn the stirling base or put it in the stove, the stirling plastic parts will damage. PRIORITY GIFT OPTION FOR MANY APPLICATIONS----It is an amazing and fantastic product at this price. Its elegant gift package makes it spruce up and presentable. It has a wide range of application as, great gift for Kids' science project, Physical/mechanical learning, teacher’s Demo props on the class, birthday gift for friends, families, parents, kids, etc. AMAZING CONVERSATION PIECES ON YOUR DESK----It's funny to see people's looks and reactions when they squeeze a little shot for this Stirling engine. Put it on the cup which full with hot waters, give the flywheel a gently push, and get the flywheel going, and then it works like charm. All of your guests want to know what happened, ice-breaking success. What a marvelous toy! It's funny to see people's looks and reactions when they squeeze a little shot for this Stirling engine. br Put it on the cup which full with hot waters, give the flywheel a gently push, and get the flywheel going, and then it works like charm. br All of your guests want to know what happened, ice-breaking success. What a marvelous toy! br br To be admired and to be talked more from your friends if you have this magic stuff. /b br This stirling engine designed reasonable and compact. You can bring it home, school office with convenient in your bag. br br Features: /b br Model: LT001 br Color: Silver plate and Gold flywheel br Speed up to 180-200 RPM br Start temperature difference: about 20°C Celsius/68 Fahrenheit br Material: carbon steel, nickel-plated carbon steel, stainless steel, glass, bronze, PVC foam and plastics br Size: 10*10*14cm/3.94* 3.94* 5.51 in br Weight:250g/0.55Ib br br br Packing list: /b br 1* stirling engine br 1* very detailed user manual br br Spare parts offer available. Only use a little graphite dry lube quiet it down nicely if there is a little noisy. You can scratch off the graphite from the pencil with a knife. br 2. Prohibit to add oil to lubricate. Because the oil will mix with dust in the air to be oil-dirt. That will make the friction to be even bigger. The stirling engine can't run freely then. br br Stirling engine is traditionally classified as an external combustion engine.