This mask fully covers the face.
It can only be placed or removed by the user while unobserved. (It can be removed by an observer by placing both hands under the mask and pulling it off.)
Once placed all observers fail to recognize the user, even if they personally know each other, regardless of identifying details including(but not limited to) clothing, tattoos, and/or name tags. Though details can be remembered and repeated by observers.
If an observer manages to remove the mask off a user, using both hands, that individual observer is immuned to the use of that individual mask, even if used by another user. Using the mask does not cause this immunity.