Smartwool Ath Artist Snow Sock, Black/Yellow size M wool Medium cushion shin and foot, 14 inch over the calf height. Flat knit durable toe seam for high burst strength, 1x1 ribbed welt, 1x1 ribbed leg. US Unisex sizing - Small (fits women's shoe size 4-6.5) Medium (fits men's shoe size 6-8.5 or women's 7-9.5) Large (fits men's shoe size 9-11.5 or women's 10-12.5) X-Large (fits men's shoe size 12-14.5) 72% Merino Wool, 26% Nylon, 2% elastane. Washer and dryer friendly! New 4 Degree Elite Fit System uses two elastics for greater stretch and recovery to keep sock in place. Strategically placed mesh ventilation zones provide temperature and moisture management. Patent pending ReliaWool Technology in high impact areas provides the longer lasting protection to keep feet comfortable.