The best undies are ones that feel barely there, comfortable enough to sleep in, sleek enough to work in, wicking enough to sweat in. The Barely Undies are just that. These undies are designed to breathe and wick but most importantly stay put all day! Poly/nylon/spandex. breathe, wick AND stay put. XS(2), S(4-6), M(8-10), L(12-14), XL(16).