nice steel 7.5cm steel kwk40 casing.
The 7.5 cm KwK 40 7.5 cm Kampfwagenkanone  40 was a German 75 mm Second World War era vehicle-mounted gun, used as the primary armament of the German Panzer IV (F2 model onwards) medium tank and the Sturmgeschütz III (F model onwards) and Sturmgeschütz IV assault guns which were used as tank destroyers.