Merino wool alpine Socks use thick piled fabric for superior cushioning. Reinforced threads provide superb durability, making this item apt for mountaineering, thru hikes, and casual weekend hikes during the winter season. In addition, merino wool's natural anti-bacterial properties provide excellent odor resistance. US Men's US Women's UK EU S 4.0 ~ 6.0 5.0 ~ 7.0 3.0 ~ 5.0 35.5 ~ 38.0 M 6.0 ~ 8.0 7.0 ~ 9.0 5.0 ~ 7.0 38.0 ~ 41.0 L 8.0 ~ 10.0 9.0 ~ 11.0 7.0 ~ 9.0 41.0 ~ 43.5 XL 10.0 ~ 12.0 11.0 ~ 13.0 9.0 ~ 11.0 43.5 ~ 45.5