Stealth Boy (Fallout)

The RobCo Stealth Boy 3001 is a personal stealth device worn on one's wrist.

Characteristics
It generates a modulating field that transmits the reflected light from one side of an object to the other, making a person much harder to see. Since it works by adding a bonus to the Sneak skill, it only has an effect while sneaking.

Uses
Nightkin NPCs can be seen using Stealth Boys, however, their usage is entirely cosmetic. Unlike the mechanics of traps, one does not have to make a saving throw in order to spot nightkins. However, if the player character uses a Stealth Boy, sneaks and begins a fight in a room with closed doors, enemies from other rooms will not join the fight.

Fallout

 * Giant Footprint special encounter - on the body of a dead peasant.
 * The Glow Level 5 - in a locker.
 * The Cathedral Tower (all floors) - on nightkin sentries.
 * Cathedral lair level 3 - in a locker.