Vital performance for fast-moving endurance athletes. They're thin and airy and made to move moisture away from skin. Felted yarn construction, with a channel weave under the foot and arch, maximizes cushion with minimal weight, advances airflow and dissipates excess heat. Ultrasoft, chlorine-free merino wool cushions the entire foot, nylon adds durability, Coolmax®, polyester and spandex improve wicking performance and aid in stretch recovery. The low-profile fit is cut higher in back for extra Achilles protection. Lintoe® seamless toe construction is a thankful detail at the end of a hot day. Made in USA.