Searchlight manufactured by General Electric. Possibly used for marine applications, or as a commercial architectural floodlight. GE manufactured a searchlight specifically for the marine trade that incorporated the same yolk but with the handle on the side.
We added the circular bottom plate so it will stand upright. The beam can be tilted up and down and by loosening the bottom pin the lamp head can be rotated. There isn't an on/off switch. Plugging it in turns it on. There is a handle on the back but the lamp is too heavy to have been designed for much carrying about.