The 14"/45 caliber gun, known initially as the Mark 1, 2, 3, and 5, and later as the Mark 8, 9, 10, and 12, were the first 14-inch guns to be employed with the United States Navy. They were installed aboard the United States Navy's New York, Nevada, and Pennsylvania-class battleships as the primary armament for each battleship in the class. The gun also saw service in the British Royal Navy, where it was designated the BL 14 inch gun Mk II.