It says size M on it, but it fits smaller. Armpit to armpit: 15 inch, total length: 22 1/2 inch. Front panel: 92% polyester, 8% spandex. Back panel/Insets/bra front lining: 100% polyester. Bra back lining: 81% nylon, 19% spandex. Bra cup: 94% polyester, 6% spandex.