Dated on the top 5-51. Opener key is still attached to bottom. Another opener is packed inside the tin. Water purification tablets small glass bottle most likely. Cigarettes from the same era.
Seldom seen and hard to upgrade the condition on this one. The item "Military C-Ration 1951 NOS RARE Korean War Cigarette Accessory Pack Tin" is in sale since Tuesday, January 21, 2020. This item is in the category "Collectibles\Militaria\WW II (1939-45)\Original Period Items\Germany\Personal, Field Gear".
The seller is "sparcs001" and is located in Clearfield, Utah. This item can be shipped to United States.