日本製鋼所
The Type 90 mounts a Rheinmetall L44 120 mm smoothbore cannon licensed produced by Japan Steel Works Limited. This is the same gun that is mounted on the German Leopard 2, the American Abrams, and the South Korean K1A1 tank. Before Rheinmetall's gun was selected, Japan had successfully produced a domestic version of the 120 mm smoothbore for testing, but the lower cost of the Rheinmetall gave it an advantage over the domestic version..