In case of injuries, the US army provides a First Aid Packet to each soldier. Each packet made of different materials throught the war, contains one bandage and one Sulfanilamide packet (A white powder to put on the wound). This type is made by Johnson & Johnson and it is rare to see it for sale! Johnson made a lot of bandage during WW2 but only few metal cased in the begining of the war (see the really clear Olive Drab paint). 
Only 4 available sadly, don't waste your chance to get one !
LAST ONE AVAILABLE