Swiftwick- Aspire Zero | Socks Built for Running & Cycling | Fast Drying, Firm Compression No Show Socks 55% Nylon 40% Olefin 5% Spandex SIGNATURE OLEFIN FIBER: Carefully selected high performance fiber that wicks moisture and will keep you dry and comfortable CONTOURED COMPRESSION FIT: Designed to support the contours of your foot. No voids, bunching, or blisters. REDUCE FATIGUE - Firm compression supports every contour of the foot to reduce fatigue during endurance activities. SEAMLESS TOE: Virtually invisible toe seam eliminates friction in the toebox. MADE IN THE USA: Swiftwick Socks are designed and crafted in the USA