The model was constructed from a set of schematics drawn by John Lambert. The model is a wire frame depicting the midget submarine Biber (Beaver). This was the smallest midget u-boat in the Kriegsmarine. The boats operated during 1944 with little success. One of the major drawbacks was the use of a petrol engine, which was detrimental to the pilot. It was unique in its hull design to encompass two G7e T2 torpedoes.