Reflective, Waterproof, Breathable, COOLMAX FX liners to keep your feet dry and comfortable. Outer Shell: 97% nylon, 2% elastane, 1% polyester. Interlining: Porelle membrane. Inner Sock: 76% COOLMAX FX, 24% nylon. Features reflective stripes around the cuff for enhanced visibility in low-light conditions, making them ideal for running, cycling, or walking. The socks are constructed with lightweight moisture-wicking COOLMAX® FX liners to keep your feet dry and comfortable in muddy or rainy weather. Be seen, be dry.