These tube tops are made of a very breathable, comfortable, stretchy cotton fabric. Far better than the 100% polyester spandex ones that feel like you're wearing a cheap plastic. They do run small, so if you usually wear a medium, you'll be better off ordering an XL. I don't wear them as tops, (as I'm not 20 anymore). I wear them under tops that are too low cut or made of sheer fabric, for layering and modesty.