Named after Klimenti Voroshilov, the People's Commissar for Defence, the KVs proved a nasty surprise for German tank crews during the early days of Operation Barbarossa. Although slow, they were extremely heavily armoured. This volume examines the transition from multi-turreted tanks to heavy single-turret vehicles, consisting of the KV-1 and 2, and the increased favour given to the heavy single-turret after the Germans began to develop ammunition...