Natural dark Brown Wool Socks are thick 100% pure new wool socks knit with sheep wool. The wool is undyed and each batch will vary slightly in colour. These thick warm wool socks are machine washable (in the delicate cycle) Zwartble wool is hardy and suitable for hiking and walking. Wool helps keep your feet feeling comfortable by preventing sweating and regulating temperature. Wool is 100% biodegradable and will compost within 18 months. Aran Knitting Wool Dark brown Available in 2 sizes: Medium : (USA 5 1/2-8 1/2) (EU 37-41) (UK size 4-7) Large : (USA 8 1/2-11 1/2) (EU 42-46) (UK size 7-11)