The original Sealskinz 100% waterproof, windproof and breathable mid length sock. Featuring Hydrostop to reduce water ingress. The inner lining is crafted from fine Merino Wool to insulate and regulate temperature making this perfect for use in colder weather conditions. Waterproof - Three layer construction for warmth, durability and waterproofing Comfort - Merino wool lining for moisture control, insulation and comfort Support - Zonal elastication for added support Comfort - Flat toe seams prevent rubbing Comfort - Footbed padding reduces pressure and absorbs shock The 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 MaterialsOuter: 90% Nylon, 10% Elastane Membrane: Aquasealz 100% Polyurethane Inner: 35% Merino Wool, 35% Acrylic, 23% Polyester, 3.5% Nylon, 3.5% Elastane