This is a nice example from the Kleinemeier house.
It's a vertical engine with a belt driven countershaft. It is supplied with a Sterno burner, which is, I believe, offered by the maker as an option to the normal Esbit burner (and is far preferable).
The boiler is 50mm diameter x approx 80mm high, with a single centre flue. It has an overflow type water level indication and a safety valve.
The steam is fed via a regulator (another optional extra) to the back of the engine frame. The single acting oscillating cylinder is 8mm bore x 20mm stroke. The crankshaft has a 53mm diameter flywheel incorporating a 10mm diameter pulley. This drives a 20mm pulley on the countershaft using a metal spring drive band. The countershaft is also fitted with a second 20mm pulley and two 9mm pulleys. The countershaft is 4mm diameter, so standard Meccano parts could be fitted.
The whole is fitted to a pressed steel base which is, itself, mounted on a wooden base (not original and has been removed since these photos).
The engine is in virtually mint condition, having been fired, apparently, only once or twice.