Help needed with ID of pilot goggles.

[kck]

I recently picked up these goggles. I really don't know anything about them any help would be appreciated. I am looking for the age, branch that would have used them and what the value might be. Thanks in advance.
Kurt

[kck]

2

[BrentNunns]

They appear to be American Mark II Pilot goggles (AN-6530) with standard nickel plated frames, and has the one piece face mask option. They were manufactured by "Charles Fischer Spring" for both military and commercial use during WW2.