Fabric - 57% Nylon, 29% Polyester, 4% Elastane (may vary with color), Recommended - Machine Wash in 40 °C / 104 °F. Avoid Bleaching or Ironing the socks. Socks will last longer if you keep them out of the dryer., Left/Right Engineered Arch Support, Breathable perfomance mesh with reflective logo for increased visibilityCondition - New The art of running demands persistence, which why Stance has created the Run. Meet their essential runner socks designed to endure the nitty gritty of every day running.