The original, 100% waterproof, windproof & breathable ankle length sock featuring Hydrostop. Perfect for use in a wide variety of weather conditions. SealSkins All Weather Ankle Length Sock with Hydrostop Features Waterproof - three layer construction for warmth, durability and waterproofing Comfort - Merino wool lining for moisture control, insulation and comfort Hydrostop - Reduces water ingress Support - zonal elastication for added supportComfort - flat toe seams prevent rubbing Comfort - Footbed padding reduces pressure and absorbs shock Hydrostop Usage Guide - SealSkinz Hydrostop technology creates a seal between the sock cuff and skin, helping to reduce the amount of water from running down the leg and into the sock ... More info