what is montana-class battleship?
A class of battleships
Montana-class battleship
The "Montana"-class battleships were planned as successors of the for the United States Navy, to be slower but larger, better armored, and with superior firepower. 
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Montana-class battleship [SEP] Introduction
The "Montana"-class battleships were planned as successors of the for the United States Navy, to be slower but larger, better armored, and with superior firepower. Five were approved for construction during World War II, but changes in wartime building priorities resulted in their cancellation in favor of continuing production of s and "Iowa"-class battleships before any "Montana"-class keels were laid. Intended armament would have been twelve Mark 7 guns in four 3-gun turrets, up from the nine Mark 7 guns in three turrets used by the "Iowa" class. Unlike the three preceding classes of battleships, the "Montana" class was designed without any restrictions from treaty limitations.