That would be correct, uses propane and air mixed in a combustion chamber/barrel [1/2 in pipe] and a bit of electronics to open and close the 2 valves and make a spark to ignite the mix. The flame and report exits the barrel. Rate of ‘fire’ is controlled by adjusting the gas mix and ignition. A re-enactors toy. Figure it would be a neat prop at WB shoots. They usually use demilled weapons for these builds. Many years ago I saw a semi 1917a1 at the Raleigh gunshow for 5000.00, i wish I had bought it now.