Sorry, now sold
This is a large model, the flywheel is approximately 11.5″ diameter, the piston diameter looks like it could be approximately 2″ diameter and the stroke is about 3 3/4″.
There is a working centrifugal governor fitted to regulator the operating speed of the engine. There is also a water pump (untested) driven by an eccentric to the main shaft. There is also a belt drive model Stuart alternator which produces approximately 2V AC at maximum engine speed.
The engine in mounted on a plinth approximately 26″ x 16″ x 3″. Overall weight must be somewhere between 35kg and 45kg.
This model can be seen in action in the following video ……