From our factory in the hills of North Carolina, DeFeet crafts these socks specifically for trail riding. Time on a bike is precious. Away from paved roads every piece of your equipment matters even more. These socks will enhance those times by giving you better performance and durability. We've used recycled plastic water bottles to make this pair mean more to the environment, too. Those who know us will not hesitate to tell you: DeFeet socks are comfortably strongerthey ride and run longer. We guarantee it. Sizing: Small Women 6 8 Medium Men 7 9 Women 8.5 10.5 Large Men 9.5 11.5 Women 11 13 Extra Large Men 12.