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! 

To be admired and to be talked more from your friends if you have this magic stuff. 
This stirling engine designed reasonable and compact. You can bring it home, school office with convenient in your bag. 

Features: 
Model: LT001
Color: Silver plate and Gold flywheel
Speed up to 180-200 RPM
Start temperature difference: about 20℃ Celsius/68 Fahrenheit
Material: carbon steel, nickel-plated carbon steel, stainless steel, glass, bronze, PVC foam and plastics
Size: 10*10*14cm/3.94* 3.94* 5.51 in
Weight:250g/0.55Ib