The 1000 Mile All Terrain Sock is a sock within a sock. The 100% Tactel inner layer stays with the foot, wicking away moisture, whilst the soft wool-cotton mix outer moves with the shoe. The lack of friction between the layers helps to prevent blisters and reduces wear. The unique combination of fibres maintains a comfortable temperature for the foot. Arch braces on both layers help prevent unwanted movement, even on severe slopes.