The German Anti-Aircraft tank - Flakpanzer IV "Wirbelwind" (Whirlwind in English).
Produced in 1944-1945. Main armament was quad Flak 38 20mm anti-aircraft guns.
The open turret was mounted on a panzerkampfwagen IV hull. It had a crew of 5 (commander/gunner, two loaders, driver, radio operator).
Operational range was 124 miles/ 200km. Maximum speed was 25mph/40km/h.