The 38 cm SK C/34[Note 1] naval gun was developed by Germany mid to late 1930s. It armed the Bismarck-class battleships and was planned as the armament of the O-class battlecruisers and the re-armed Scharnhorst-class battleships. Six twin-gun mountings were also sold to the Soviet Union and it was planned to use them on the Kronshtadt-class battlecruisers, however they were never delivered.