Stealth Boy (Fallout 4)

Stealth Boy is a consumable item featured in Fallout 4.

Characteristics
The Stealth Boy is a portable device that, when activated, renders the user invisible for about 30 seconds and an extra 12 seconds more with the Cloak & Dagger perk (need verification).

Unlike variants of the Stealth Boy found in the Capital and Mojave Wastelands, this version isn't worn on the wrist. Instead, it is activated by hand and is held on the waist, like a satchel.

Locations

 * Sold by Tinker Tom in the Railroad HQ, who also sells the Railroad Stealth Boy variant, which lasts 10 seconds longer.
 * One is found in Park Street station. To find it, 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 within.
 * One stealth boy can be found at the end of the Tradecraft mission beside the Carrington's prototype.
 * One stealth boy can be found in the ArcJet Systems building.
 * One Stealth Boy can be found in Back Street Apparel. After entering the building, enter the first door on the left.  After picking the locked door in the hallway, it will be on the shelving to the right. This location respawns, so more can be obtained.
 * A Stealth Boy can be found in Federal ration stockpile. After entering, at the first intersection of hallways (with the construction light, just past the two can traps), turn right. Go down the stairs to the metal walkway, then jump across the gap.  The Stealth Boy is by the two skeletons in the room on the other side of the gap.
 * One can be found in the National Guard training yard upstairs in the smokey room. It is near the large trunk. Location respawns.
 * Two can be found at the castle armory behind the large metal door. The armory is accessible both during and after the Old Guns quest.
 * One can be found on the desk in the medical lab in secret Vault 81.
 * One can be found next to a dead soldier in the Boston mayoral shelter.
 * One can be found upstairs, in an Expert locked caged room, on a shelf, at Wattz Consumer Electronics.
 * One can be found in the locked storage room of the Boston Public Library.
 * Up to three can be found on Kellogg after defeating him.
 * One can be found in the Hesters Consumer Robotics building, in a case on the racking in the entrance room.
 * One can be found in an advanced locked safe in the dark storage room behind the counter in Backalley Lanes in the General Atomics Galleria.
 * One can be found in the Suffolk County charter school downstairs area, behind a locked Security Gate.
 * One can be found in Edwin's safe, at Chestnut Hillock Reservoir, outside of Diamond City. Key can be acquired below the capsized boat.
 * One can be found on the top floor of D.B. Technical High School. This location respawns, so more can be obtained.
 * One can be found in a Master locked safe on the second floor of a small house in Revere Beach station, along with a Legendary Raider.
 * One can be found in Recon Bunker Theta, during The Lost Patrol quest.
 * One can be found inside a safe in the Gift Shop Basement in the Walden Pond.
 * One can be found in the BADTFL regional office in the evidence locker. Respawns.
 * Three can be found at the end of The Big Dig inside Hancock's stockpile. Can only be obtained if the player sides with Bobbi.
 * One can be found upstairs in Hardware Town behind the locked door. The key is found in a chest a few rooms down. Location respawns.