First off, I am NO Allied air force gear expert but I believe this is a USAF cold weather mask for waist gunners in open gun ports.
A bit mothed / silverfish nipped but all there. I thought it was a bit rough around the eye holes until I read the label .......
so I guess it WAS issued but maybe not used much?
Happy to hear your thoughts - and, it will end up in the classifieds soon as it's not what I collect.