What is an Integrated Steam Plant?

What is an Integrated Steam Plant?
In MSM terms it is an assembly of properly matched components fitted to a brass mounting plate that can be operated as supplied - just by adding connsumables, items like gas, water, and oil. 
Given the consumables, the plant can be operated on the bench.
Physically, in a properly planned model boat, it can be fitted into the boat, the crankshaft connected to the propeller shaft, the RC links connected and the model is ready for the pond!
You will recognise the simplification implied here but, excluding the otherwise trivial items. Our Integrated Steam Plants are "Install & Run" - no if's & buts!!