The Flakpanzer IV "Wirbelwind" (Whirlwind in English) was a self-propelled anti-aircraft gun based on the Panzer IV tank. The Panzer IV's turret was removed and replaced with an open-top, nine-sided turret which housed a quadruple 2 cm Flakvierling 38 L/112.5.  Thereafter, the 2 cm shells proved less effective against aircraft so a more powerful successor was produced which eventually replaced it. Known as the Flakpanzer IV Ostwind (East Wind), the successor was equipped with a single 3.7 cm FlaK 43.



Flakpanzer IV "Wirbelwind"

Two wrecked Panther tanks (Panzerkampfwagen V Panther) of the Wehrmacht's 130th Panzerlehr Tank Regiment on a road in Normandy, France.

Wrecked Panther tanks

A PzKpfw IV Ausf. F2 belonging to the 12th Panzer Division in the Volkhov's pocket, Northern Russia, photo taken between March and November 1942. In this photo we can see two of the main characteristics that allow to distinguish between a Ausf. F2 and later variants of the Pz IV: The single baffle muzzle brake, unique to the F2 and the turret side vision ports (above the n. 631) that were absent in later variants, the exception being a couple of Ausf. G's that were fitted with excedent F2 turrets in times of need.