Adjustable Speed Stirling Engine Model Hot Air External Combustion Engine FG

Adjustable Speed: When the engine is running normally, the speed of the engine can be adjusted by turning the knob on the top of the engine. Easy to Operate: Install the two knobs, add two thirds of 95% fuel (not included) to the fuel lamp, ignite it, heat it for 30 seconds, then turn the flywheel, and the engine can run.

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