 The light AA armament of the Fusō class changed dramatically from 1933 to 1944 . During the first reconstruction , Fusō was fitted with four quadruple 13 @.@ 2 mm ( 0 @.@ 52 in ) machine @-@ guns , while Yamashiro was fitted with eight twin 25 @-@ millimeter ( 0 @.@ 98 in ) gun mounts . Both weapons were license @-@ built French Hotchkiss designs . The 25 mm guns were mounted on the Fusō class in single , double and triple mounts . This model was the standard Japanese light anti @-@ aircraft gun during World War II , but it suffered from severe design shortcomings that rendered it a largely ineffective weapon . The twin and triple mounts " lacked sufficient speed in train or elevation ; the gun sights were unable to handle fast targets ; the gun exhibited excessive vibration ; the magazine was too small , and , finally , the gun produced excessive muzzle blast " . The configuration of the anti @-@ aircraft guns varied significantly ; by the end of their final reconstruction , the Fusō class mounted eight twin mounts . In 1943 , seventeen single and two twin @-@ mounts were added for a total of 37 . In August 1944 , both were fitted with another twenty @-@ three single , six twin and eight triple @-@ mounts , for a total of 95 anti @-@ aircraft guns in their final configuration . 
