Considered as Germany's most important tank during the WWII, the Panzerkampfwagen IV or "Panzer IV" initially operated as an infantry support tank. However, due to the ineffectiveness of the Panzer III against the Soviets' T-34 tanks, the Panzer IV took its cousin's place and remained in continuous production from 1936 to 1945. Throughout its long reign, the Panzer IV experienced numerous upgrades and design modifications. The Ausf.H started production in April 1943. A total of 3,774 units of this tank were made. It featured a six-speed SSG77 transmission, which was taken from the Panzerkampfwagen III. This increased the tank's weight to to 25 tonnes.