Swiftwick One Vibe Pewter/Olympic Blue/Grey, XL - Men's 46% nylon MADE IN THE USA: Swiftwick socks are made in the USA, an important commitment we make to our customers and local communities. Purchase includes one pair of socks. SIGNATURE OLEFIN FIBER: Made of high-performing, lightweight Olefin fiber that wicks moisture and dries quickly. Abrasion resistant, strong and colorfast. Material composition is 46% nylon, 45% Olefin fiber and 9% spandex. ARCH BAND SUPPORT AND THIN UPPER: The arch maintains shape to deliver lasting support. Thin upper is flat knit and light to improve breathability. FLEX ZONE: Half-density weave prevents bunching at flex points. Y-HEEL CONTOUR AND SEAMLESS TOE: Y-shape stitch creates a contoured heel pocket that moves with the foot. Virtually invisible toe seam eliminates friction in the toebox.