Differential pressure controller

The differential pressure controller is a quest item $$

Gameplay
The differential pressure controller is found in Vault 11, and is used for repairing the air filtration system in Brotherhood of Steel's Hidden Valley Bunker for the Still in the Dark quest.

Location
The differential pressure controller is located in one of the first rooms encountered on the lowest level of the vault, flooded with water (air pockets exist towards the ceiling). It will be stashed in a locker, close to the overseer's office, and can be found before the quest has been initiated.