Mercury/Mariner Power Trim Unit 893518t01
Power Trim Unit
This came off a Mariner 40hp Fourstroke, will also fit the 30hp. It may fit other Mercury/Mariner engines.
I don't know the history of this unit, or why it was replaced, but it appears to operate when put on a power supply.
Good source of parts or for repair as these are expensive units, over £1000 for a new one from Mariner.
Can post, but is quite heavy.