Covert Threads Desert Climate Military Boot Socks, Brown, Large Silver Lining in Heel and Toe helps prevent Infections and fights Foot Fungus, Absorbent Acrylic helps keep feet dry all day Stay Up Top w/ hugging support all day, Thick Wool Cushion heel pad and toe for relief of High Impact Special wool fights friction and hot spots helping prevent blisters, Built - In Arch Support made for the long haul, special "Y" heel for better fit to the contour of the foot Instep Flexzone to prevent bunching of the sock. Contents: 44% Wicking Acrylic / 28% Wool / 19% Nylon / 2 % Polyester / 5% Lycra Spandex/ 2% Silver Lining Made in the United States of America