This mod adds a water breathing effect to all power armor helmets (and the space suit helmet). No other requirements; just put on the helmet and swim to your heart's content.
Affects the player character only. As far as I know, followers can't drown anyway.
Note: You won't see "Water Breathing" on the list of effects for the helmet itself. You will, however, see "Water Breathing" on the "EFF" page on your Pip-Boy's Stats screen, and you'll also see a message saying "Water Breathing added" when you put on a suitable helmet. It's done this way to maximize compatibility with other mods.
Affects the player character only. As far as I know, followers can't drown anyway.
Note: You won't see "Water Breathing" on the list of effects for the helmet itself. You will, however, see "Water Breathing" on the "EFF" page on your Pip-Boy's Stats screen, and you'll also see a message saying "Water Breathing added" when you put on a suitable helmet. It's done this way to maximize compatibility with other mods.