This consisted of Nendo Shiki (third year type) 15,5 cm/60cal guns. Engineer C. Hada designed the 15.5cm guns (as weel as the 46cm guns) in 1932 as the maim armament for B class cruisers; they were also mounted in the Mogami class cruisers.these guns were the finest in use during the second Wold war. Yamato and Musashi originaly had four 15.5 cm gun turrets. these triple turrets were made available by the conversion of four Mogami class cruisers, which were given twin turrets with 20.3cm guns in place.The triple turrets after modernisation were installed in a diamond arrangement,the turrets in superfiring positions over the main battery for and aft, and the two others were in wing positions, one on each side.The wing turrets were removed to provide space for additional 12.7cm AA guns for Yamato in january 1944 and for Musashi in April 1944.