What appears to be a small building is actually a small portion of the actual building left above ground. Near the locked door, there is hole descending into the upper level of the building itself. The location consists of a few small rooms over two levels. At the bottom level is a room with an empty power armor station, and a terminal which allows unlocking the room on the surface where 2-4 high level ghouls are located.
To the right of the terminal is a sentry bot model which can be found and assembled.
O'Neill Family Manufacturing only appears in Fallout 4.
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