Breastplate

primarily, "the breast," denotes "a breastplate or corselet," consisting of two parts and protecting the body on both sides, from the neck to the middle. It is used metaphorically of righteousness, Eph 6:14; of faith and love, 1Th 5:8, with perhaps a suggestion of the two parts, front and back, which formed the coat of mail (an alternative term for the word in the NT sense); elsewhere in Rev 9:9, Rev 9:17.