They're a runner, they're a track star, they are this delightfully fun half binder! If you want to compress your chest and and be able to "jump! jump!" look no further than this Criss Cross design. Can be worn under clothes, as a top alone, or while ascending any podium for recognition of your achievement in being hot. Details: 84% Nylon, 16% Spandex, Latex Free Moisture Wicking Technical Fabric Cotton Blend Lining Each piece can bind/compress about 3-4 cup sizes (3-4 inches off bust measurement) Hand wash is preferred, but if not, machine wash cold. First model measures wears an XS with a 27" rib measurement and a 31" chest measurement, the second model wears a Large and has a 35" rib measurement and a 44" chest measurement Binder Safety: Above all, we recommend listening to your body! If the compression ever feels excessive, or causes any pain, remove immediately.