Smartwool Men's PhD Outdoor Heavy Crew Sock, Oatmeal/Brown size M(shoe size 6-8.5) wool Heavy full cushioned Phd Outdoor Crew for men is a versatile sock, thanks to WOW Technology in high density impact zones, shock and abrasion are reduced. The 4-Degree Fit System keeps the sock in place. Men's sock sizes - Medium (fits US shoe size 6-8.5) Large (fits US shoe size 9-11.5) X-Large (fits US shoe size 12-14.5) 86% Merino Wool, 12% Nylon, 2% Elastic, washer and dryer friendly