These tank top are 85% polyester and 15% spandex, no bra insert, and they are machine washable. The sizes run larger so if you like a “tightly fit feel” please order one size smaller then you normally wear. You are able to move without restrictions with their comfortable stretchy fabric. They are soft, breathable, and are moisture-wicking to help keep you dry no matter how much you sweet. The perfect option for various indoor activities or outdoor excursions such as yoga, sports, running, cross-training or any other activity. They come in a variety of different colors.