This sports bra carries many of the features of other Zensah products (anti-odor, moisture wicking, breathable, light compression) and is seamless to prevent chafing. Wide straps prevent dig in and the racerback design allows for movement. Small/Medium is 32 ABC - 34 AB, Medium/Large is 34 ABC - 36 AB, and Large/Extra Large is 36 ABC - 38AB. Specs: 94% nylon, 6% spandex