That is interesting. I would think this would be for high altitude aircraft. Probably bomber crews. Nice find.
The removed label in one of the pics would make me do as much research as possible to confirm what date it is. Nice item whenever it is from, but I assume if post war that would affect its value and desirability.
Whatever its just an opinion.
Im sure I can just make out a faint 40 there on the faded ink stamp
2. size 40?
I did go grab it and took it outside in the light... the number is definitely a 40. Who knows if that the date or not...