1000 Mile All Terrain Socks - SS19 Tactel inner layer - Stays with the foot and wicks moisture to keep you dry and comfortable. Wool-cotton mix outer - Moves with the shoe to reduce irritation and wear. Top venting - Increases breathability. Arch braces on both layers - Reduce unwanted movement. Material - Outer layer: 45% merino wool, 42% cotton, 12% nylon, 1% elastane Lycra. Inner layer: 100% Tactel.