This is the shorter, K-ration style D-ration that was used in the K-rations after 1943.
Initially the standard 2 oz D-ration was included in the K-ration. However, the original 2 oz D-bar was too long compared to the crackers and tended to break through the cellophane pack. To solve the problem, in 1943, the confections were made to fit a standard size that would better fit the cellophane insert. The result was a shorter, stubbier bar.
The mold was made using original blueprints, measurements, and specifications. Dummy chocolate sold separately.