It was the main anti-tank weapon of Wehrmacht Panzerjäger units until 1942. Developed by Rheinmetall in 1933, it was first issued to the German Army in 1936, with 9,120 being available by the beginning of the war in September 1939 and a further 5,339 produced during the war. As the predominant anti-tank gun design in the world during the late 1930s, demand was high for the Pak 36, with another 6,000 examples produced for export and the design being copied by the Soviet Union as the 45 mm anti-tank gun M1932 (19-K) and by other nations such as Japan.[1]