So there is a fire in your office block, you are stuck on the 29th floor, and you are engulfed in choking dark smoke. You need an air supply. Well if you happen to have one of these gizmos in your back pocket, might just survive long enough for the firemen to save you. Honestly though, I think I would rather chance it and jump out a window, or even suffocate to death, then use a toilet pipe air supply. Imagine, some guy didn’t flush.