The Panzerkampfwagen IV (Pz.Kpfw. IV), commonly known as the Panzer IV, was a medium tank developed in Nazi Germany in the late 1930s and used extensively during the Second World War. Its ordnance inventory designation was Sd.Kfz. 161. German medium tank the SdKfz.1611 Panzerkampfwagen IV (Ausf. F2 models onwards).