Responsive feel in a thin, lightweight design. Swiftwick's most popular running sock and a great no-show cycling sock. The ASPIRE is engineered with firm compression and a thin profile for a responsive feel. Firm compression supports every contour of the foot to reduce fatigue during endurance activities. Zero cuff height sits below the ankle with minimal extension above the shoe. Thin profile with light cushion Channeled upper improves breathability Lightweight Olefin fiber wicks moisture and dries quickly 55% Nylon / 40% Olefin / 5% Spandex