Mitsubishi Heavy Industries reports its delivery on Monday of its fourth Soryu-class submarine to Japan's Ministry of Defense.
Japan currently has seven of the submarines.
Soryu-class submarines are the world's largest conventionally powered submarines, equipped with state-of-the art technologies, including air-independent propulsion systems.
The submarines are 274.5 feet long, about 29.8 feet wide, and have a maximum speed of 20 knots.
The submarine delivered on Monday -- the Jinryu -- was the fourth Soryu-class vessel by MHI, which has manufactured a total of 26 submarines at its Kobe facility over the past 70 years.