The standard medium, self-propelled anti-aircraft artillery piece of the Soviet and East German armies of the late 1960s was the ZSU-57-2: essentially a lighter variant of the T-54-chassis, mounting twin 57mm S-60 autocannons – the most powerful anti-aircraft gun installed on a self-propelled chassis at the time – in an open-topped, box-like welded turret. Contrary to the T-54, the vehicle was lightly armoured (13.5-15mm on hull front and sides, and 13.5mm on the turret). Two batteries of four ZSU-57-2s were assigned to every tank regiment, but relatively few saw service in motorised rifle formations. As usual, all were painted in dark olive green and received vertical identification stripes in white for the duration of Operation Danube. (Artwork by David Bocquelet)