Commissioned in 1921, the IJN Nagato-class battleship Mutsu displaced 42,850 tons and could cruise at 27 knots. Along with the Nagato, she was the first class of battleship in the world fitted with 16" (40.64cm) guns. Relegated primarily to training and support duties throughout WWII, she met a rather ignominious end on June 8, 1943, when her #3 turret's magazine exploded while moored near Hashirajima. Only 353 of the Mutsu's 1,474 crewmembers survived the explosion and subsequent sinking.
Aoshima's waterline kit represents the Mutsu as she appeared at Hashirajima in 1943. With the exception of a few conning tower parts, this kit and the simultaneously re-released Nagato kit are identical.