''Developed by the United States Navy as the main gun of their treaty heavy cruisers, it was equipped on them in a triple mount.<br>It possesses great firepower even though it is just a basic mounting of three 20cm guns in a single turret.<br>It was used as the main gun of the USN's Pensacola and Northampton-class treaty heavy cruisers. | ''Developed by the United States Navy as the main gun of their treaty heavy cruisers, it was equipped on them in a triple mount.<br>It possesses great firepower even though it is just a basic mounting of three 20cm guns in a single turret.<br>It was used as the main gun of the USN's Pensacola and Northampton-class treaty heavy cruisers. |