Board Thread:Questions and Answers/@comment-173.17.126.12-20170907051655/@comment-27862274-20170907060843

Upgraded equipment gives additional stat bonuses that are not visible on the equipment screen. The higher the number of stars the higher the stat bonus, though note that the stat bonus is of diminishing returns (rooted if i remember correctly). When the game does damage calculations they will take these bonuses into account, but the 100 ASW requirement for OASW will not take into account upgraded stats.