Sd.Kfz.131 Panzerjager II fur PaK 40/2 Marder II Mid Prod. Early in the war there was an urgent need for self-propelled anti-tank platforms, especially when the Wehrmacht was confronted by well-armored enemy vehicles such as the T-34 and KV-I during the invasion of Russia. Many hybrid designs were converted from obsolete tank chassis. The Marder II was a case in point, as it was based on a Panzer II chassis. The Mid-Production version of the Marder II (Sd.Kfz.131) was armed with 7.5cm PaK 40. Some 576 Marder IIs were produced from June 1942 till June 1943, and they fought primarily on the Eastern Front.