20.3cm Twin Gun Mount
Introduction
重巡に搭載された主砲、それが20.3cm連装砲です。
条約上限一杯の8インチ（20.3cm）のこの砲は、中距離での砲撃戦はもちろん、
夜戦のような近距離での殴り合いでも十分にその威力を発揮します。
限定的ですが、対空射撃も可能です。
"The 20.3cm twin gun was the main armament of heavy cruisers. Calibered at 8 inches (20.3cm), the limit of naval treaty, it works extremely well in both day and night battle, from point-blank to mid-range firing. It also works limitedly as anti-air weapon."
Equipped as standard main guns for all Japanese heavy cruisers. Initially it was developed as the 20.0cm single mount (as seen on early Furutaka-class cruisers) but was later modified to fit 8.0 inches (20.3cm). "
Note
Buildable