This is a simple steam plant utilising the Unit Steam Engine in combination with a small pot boiler.
The boiler is made of copper and is 50mm diameter x 100mm long. It is unusual in that it hinges up on one end to gain access to the two individual tablet burner trays. I'm not sure if this is a good, bad or indifferent idea. It has a mamod style safety valve and overflow water level plug. The steam line exits from the bottom of the boiler and passes through the flame, giving a small degree of superheat. The pipe exits the firebox at the hinged end and is connected to the Unit Steam Engine via a flexible pipe. The boiler is covered with a copper cowling which channels the heat right round the boiler.
The engine is a standard Single cylinder Unit Steam Engine (see HERE). It has a pair of pins attached to the flywheel to couple it with a propeller shaft.
Condition is good and appears to have seen little use. After a good running in session, it runs quite well.