Darn Tough Vermont Merino Wool Dress Crew Sock 55% Merino Wool,42% Nylon,3% Lycra Spandex Made in Vermont, USA Unconditional Lifetime Guarantee Performance fit and Unsurpassed durability Men's Sizes: Small 5.5-7.5, Medium 8-9.5, Large 10-12, X-Large 12.5+