''This is a group of additional firearms that improves the survivability of fleet oilers, submarine tenders, amphibious assault ships, repair ships, etc. on the battlefield.<br>Although it is equipped with old-style firearms and regular machine guns, it is possible to increase the resistance of a weak and low-armed surface ship against attacks from enemy air forces on the front lines or during navigation.<br>In addition, when operating on these low-armed ships, it is possible to improve their effectiveness with [[improvement]]s.