The 3.7 cm PaK 36 (Panzerabwehrkanone 36) is a German 37mm anti-tank gun. It was developed in the 1920s by the Rheinmetall concern, it entered service in 1928. In 1936 it received the designation Pak 35/36. Under the designation of 3.7 cm KwK 36 L45, it was mounted in the Pz.Kpfw III Ausf tanks. AG. At the time of its entry into the German army, it was a very modern weapon. However, over the years, its quality and effectiveness against new tanks decreased. The gun turned out to be weak during the September campaign, and during the "Blitz" in the West in 1940 it was completely useless against many Allied tanks. For this reason, it gained the unflattering nickname "door knocker". However, it survived in the German army until the operation "Barbarossa" and fought against the T-34 and KW-1, showing its utter uselessness. From 1941, it was systematically replaced by the Pak 38. Technical data: range: 7000 m, caliber: 37 mm, combat weight: 328 kg, initial velocity: 762 m / s, rate of fire: 13 spins / min.