Stealth Boy (Fallout 4)

Stealth Boy is a consumable item featured in Fallout 4.

Locations
It is found in Park Street Station once you head downstairs, go straight across all the tracks and there will be a locked room on the left as you reach the far wall requiring novice lockpicking. Once inside there is a safe towards the back of the short tunnel requiring expert lockpicking and the device is located in there.