This Stirling engine is a heat engine that operates by cyclic compression and expansion of air at different temperature levels. The burner heats the glass tube causing the displacer piston to be pushed out, allowing the air to flow into the adjacent cylinder and be cooled by the alloy fins which in turn draws the metal piston upward in it's cylinder to complete the cycle. The simple stirling engine is a great looking working model to display on a shelf with its Nickel plated finish and CNC machined brass and alloy components, it's a great way to amaze visitors or teach others about internal/external combustion engines. You will need only Methanol or Methylated spirit to power the engine.