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). 
In the course of 1943, the medical dept. take a rather radical step by adopting laminated paper and a lead foil wrapper to simplify the manufacturing process and of course economise metal alloys usage. 
This first type with blue markings was made by Acme Cotton Products Co. and comes with its card box. 
A great piece to complete a first aid pouch !