The Panzerkampfwagen IV Ausf.G (in-game Panzer Tank (AP)) is an AP-type tank, meaning that it is more effective against tanks. It can be built in World War II. Like other AP tanks, it is more expensive than HE tanks. Still, it should not be used against anti-tank siege weapons. It is interesting enough that the Panzer is stronger than the Sherman. This is probably an allusion to how German Panzers destroyed many Shermans during the war. In the end, the Panzer Tank can be used to portray other German tanks, not only the Panzer IV.
Note that the in-game model is missing two bottom wheels, making the tank look like a modified Panzer III.