Standard Non-Rebreathing Oxygen Mask,(Pack of 10), Rebreather Oxygen Mask (Adult)

This is exactly what you'd expect. It is a commodity grade non-rebreather mask. It has valves so that you don't exhale any air into the accumulator bag. And valves to keep you from inhaling air from anywhere but the bag. (Curously, the masks sold without the bag have the same holes on the side where the valves go, they just don't attach the valves to them).The main issue with these is the acrid odor they have. It's not unusual for O2 masks and cannulas to have it, but I wish they didn't. I'm hoping they will out gas because it is kind of unpleasant, especially in a mask where all your air has to come through the mask and bag.