A breastplate (or similar piece of chest armor) with individually molded breast cups. Although more practical than bikini armor due to at least covering the skin, it would have the undesirable tendency to direct attacks into the wearer's sternum rather than deflecting them away like real armor.
This tag should not be used for armor that would qualify as bikini armor. A boobplate should still cover a significant portion of the torso and not just the breasts. For armor that only covers the breasts and leaves most of the upper body exposed, use the bikini armor or chest guard tags instead.
Notable examples of characters who wear a boobplate include Darkness from Konosuba, Catherine from Fire Emblem: Three Houses, Noelle from Genshin Impact, and Mash Kyrielight from Fate/Grand Order.