Dachstein Woolwear 100% Austrian Boiled Wool Extra Warm Over the Knee Socks Made in Austria of 100% boiled wool essential for comfort in cold weather since wool can absorb 30% of its weight in water and maintain its insulating qualities. Socks are European, but listed here in US Men's Shoe Size for convenience. Hand wash in cold water with natural soap and air dry flat and your Dachstein Woolwear product will last a lifetime. Please do not use the Amazon size chart for reference. See additional images for the Dachstein Woolwear size chart. The Grey socks are Extra Warm3 ply wool and the Green socks are Extra Warm 3 ply wool