The rebreather provides a Damage Resistance of 3, but no DT, and grants unlimited oxygen while submerged underwater. The player cannot drop or sell this item, and its condition will never degrade. It fills the mask slot, so it does not prohibit the wearing of headgear that only covers the top of the head (e.g., combat helmets). It cannot be worn with certain helmets, such as power armor helmets, or glasses (e.g. Dr. Mobius' glasses), but can be worn with most hats.
The rebreather is located in the apparel section of the Pip-Boy and cannot be worn in conjunction with any kind of eyewear, but it can be worn with most headgear such as the space suit helmet or the combat helmet. Interestingly enough, since the goggles helmet can be worn with glasses, it can also be worn with the rebreather. It also fits on Chinese stealth armor.
If one fails Jack's mission or if Janet is killed, when trying to gain the Boomers' respect, he will only say "Go to hell, outsider. Stay away from me" which means one cannot communicate any further with him, and making the obtaining of the rebreather difficult. He can still be spoken to, however, if the Courier approaches him when he goes home to sleep.
Upon completing the quest Volare!, the rebreather is still considered a quest item and therefore cannot be dropped, sold, or placed into any storage devices. As such, it can be taken to the Sierra Madre. The quest flag can be removed by using the console command SetQuestObject 00100633 0.
The rebreather is not an air filtration system, and cannot protect from the Cloud in the Sierra Madre.
If the player character's nose is big enough, it will poke through the mask.
The rebreather may sometimes be grayed out in the equipment list, thus appearing to be too damaged to be used without repair. This is purely a display bug and has no effect on its functionality. [verified]
After equipping the rebreather for the first time, if you unequip it any time before saving, your DT may not appear in the slot at the top of the screen under the Items menu in your Pip-Boy 3000, regardless of what else you are wearing. Only when you re-equip the rebreather does DT (and DR) reappear. This can be fixed by saving (confirmed on PS3) or rebooting the system (confirmed on Xbox) or unequip the rebreather when it says "DT" not "DR". [verified]