Asos shift dress dark gray and metallic gold

This Asos shift dress is in GREAT preowned condition size 6 pit to pit 20" length 34¾" waist 20.5" arm opening 7" I can wear dress sizes 4-6 but this dress is very boxy on me and the arm opening seems big for size 6 dress: 83% polyester 37% viscose trim: 53% cotton 47% polyester dark gray and metallic gold gray part has a bit of stretch, gold part does not