It's my understanding that the process makes the valves.

I think that the idea is to be able to make masks for yourself for things like being on buses, stores etc. However I'm not trying to over think these kinds of things. I don't have a printer and I just maintain distance between myself and other folk.

About beards---when I was in the Navy, beards were allowed, but when I was in Submarine School, the petty officer who was teaching about the OBA (Oxygen Breathing Apparatus) had a full beard and he pointed out that if he was ordered back to sea that the beard would be the first to go as it wouldn't allow a good fit of the OBA.

Just common sense in my mind.