12.8cm Flakzwilling 40/2 German Heavy Anti Aircraft Gun
Developed in 1936 by Rheinmetall-Borsig, the first prototype Flak 40 was tested in late 1937. Its weight was nearly 12 tonnes which made the gun difficult to transport. In addition to the single barrel Flak40, a twin gun version was also produced as the 12.8cm Flakzwilling 40/2. The Flak 40 entered service in 1942 being used in Flak Towers to protect Berlin, Hamburg and Vienna. Perhaps the most famous tower being the Zoo Tower in Berlin which mounted four Flakzwilling 40/2 - one on each corner.