Original Item: Only One Available. This is an excellent example of a rather rare wooden crate that would have contained 12 K-Rations. The box is in wonderful condition and retains mostly legible stamping on the front and side. The box was manufactured by the Cracker Jack company.

The box measures approximately 12 ½” x 22” x 7 ¾” and would make for a wonderful addition to any WWII G.I. collection! Comes more than ready for further research and display.

In 1941, Ancel Keys, a University of Minnesota physiologist, was assigned by the U.S. War Department to design a non-perishable, ready-to-eat meal that could fit in a soldier's pocket as a short-duration, individual ration. Keys went to a local supermarket to choose foods that would be inexpensive, but still be enough to provide energy. He purchased hard biscuits, dry sausages, hard candy, and chocolate bars. He then tested his 28-ounce (800-gram), 3,200-kilocalorie (13,000-kilojoule) meals on six soldiers in a nearby U.S. Army base. The meals only gained "palatable" and "better than nothing" ratings from the soldiers, but were successful in relieving hunger and providing sufficient energy. The new rations were initially intended as individual rations suitable for short durations only, to be used for a maximum of fifteen meals before supplementation or replacement with 'A-ration' or 'B-ration' field rations. They were soon called the "paratrooper ration", since paratroopers were the first to be issued the ration on an experimental basis.

The actual prototype of the K-ration was a pocket ration for paratroopers developed by the Subsistence Research Laboratory (SRL) at the request of the U.S. Army Air Forces (USAAF) early in the war. Two original samples (one version used pemmican biscuits, a peanut bar, raisins, and bouillon paste; the other used pemmican biscuits, a small D ration bar, canned processed meat, and lemon beverage powder) evolved into the one-package breakfast-dinner-supper combination later adopted as standard. The Quartermaster Command's Subsistence Branch altered some components and renamed the ration the Field Ration, Type K, or "K-ration"; the final version totaled 2,830 kilocalories (11,800 kJ). The first procurement of K-rations was made in May 1942. Some believed the K-ration was named after Dr. Keys or was short for "Commando" (as elite troops were the first to receive it). However, the letter "K" was selected because it was phonetically distinct from other letter-name rations.

The K-ration first saw use in 1942, when it was issued to U.S. Airborne troops on an experimental basis. Initial reports praised it for the variety of the foods incorporated, as well as the light weight. However, testing in extreme climatic and operating environments was extremely limited: in jungle testing, for example, the K-ration was evaluated in Panama by paratroopers and the Panama Jungle Test Platoon in an experiment lasting only three days. Marching was done not through jungle, as might be expected, but only on flat or gently rolling terrain on cleared roads, for an average of only 11 miles (18 km) per day. The test platoons carried one K-ration, weapon, poncho, shelter half, and a single filled one-quart canteen. No testing was done of men on extended patrols or with heavier individual loads of ammunition and water. At the end of the three days, the men were weighed, and as no abnormal weight loss was noted, the K-ration was deemed successful. These findings were later used in 1943 to support a decision to discontinue production of the Mountain ration and the Jungle ration. Both of these specialized rations had proved costlier to produce in their original form, and were intensely disliked by the Army's Subsistence Branch staff of the Quartermaster Corps, who had to secure additional supply contracts and storage facilities for the new rations. Though the K-ration was designed to be an emergency ration, Quartermaster Corps officials would continue to insist until the end of the war that the K-ration would satisfy all requirements for a lightweight complete field ration for all front-line troops at a scale of one K-ration per man per day, using the prior experiments with airborne forces as evidence. The ration's intended use as a short-term assault ration would soon fall by the wayside once U.S. forces entered combat.

One major criticism of the K-ration was its caloric and vitamin content, judged as inadequate based on evaluations made during and after World War II of the ration's actual use by Army forces. There was also a danger of over-reliance, which could cause the three meals to become monotonous if issued for long periods of time. The K-ration allowance was one ration per man per day (breakfast, dinner and supper), because of the short duration and hasty nature of experimental testing of the K-ration before adoption. Ration planners did not realize that soldiers fighting, digging, and marching in extreme conditions would require many more calories per day than a soldier marching over cleared roads in temperate climates. Nevertheless, one K-ration per man per day would remain the basis of issue, even for mountain troops fighting at high altitudes and infantrymen fighting in the thick jungles of Burma. Military personnel also supplemented with various other rations throughout the war such as with the C-ration when needed.