The chocolate bars shown are not of the type issued to GIs in the Korean theatre, Standard milk chocolate was found to melt far too easily and so the United States Army turned to Hershey for help in developing its survival Field Ration D bar, it was only natural that in 1943, the Procurement Division of the United States Army approached Hershey Chocolate Corporation about the possibility of developing a heat resistant confectionery chocolate bar with an improved flavor. After a short period of experimentation, Hershey's Tropical Chocolate Bar, in one and two ounce sizes, was added to the list of war production items. The label was a type of glassine paper, white or tan, printed with brown ink with the exception of the word "Tropical" which was printed in red.
Hershey's Tropical Chocolate bars were developed to provide military personnel with access to a confectionery treat in parts of the world where Hershey's traditional products would readily melt. The Tropical bar's product formula was designed to allow the bar to hold its shape after one hour in 120 degrees Fahrenheit.
This bar was destined to exceed all other items in tonnage produced and along with the Field Ration D bar, became part of Hershey Chocolate's history. By the end of World War II, almost 380,000,000 two ounce Tropical bars had been produced for the United States military.