The weapon was originally designed for ship use and was produced in large numbers. The gun was also adapted for land use as a dual-purpose gun. It was one of the few Japanese cannons that could readily handle more heavily armored allied tanks such as the sherman. The barrel was of
autofretted mono-block construction and was held in a sleeve cradle mounted on a pedestal mount which permits 360° of traverse. The gun uses a
hydro-spring recoil mechanism attached to the sleeve cradle and there are three recoil cylinders located on top of the breech with the two outside cylinders housing the recoil springs, and the center cylinder housing the hydraulic recuperator. The elevating handwheel is on the right side of the mount, while the traversing handwheel is on the left. To compensate for muzzle
preponderance, spring
equilibrators are mounted below the gun barrel. The gun is said to be well balanced, and easy to elevate. A semi-automatic horizontal
sliding-wedge breech is used and
Fixed QF 120 x 708R ammunition was used. The gun fired either high explosive or incendiary shrapnel shells that weighed , with a complete round weighing . ==Naval use==