Covert Threads Desert Climate Military Boot Socks, Black, Large Absorbent acrylic and wool keep feet dry all day. Silver Lining in heel and toe helps prevents Infections and fights foot fungus. Special wool fights friction and hot spots, helping prevent blisters. Designed to eliminate hot spots and absorb toe and heel impact. 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. Stay-up top with hugging support all day. Thick wool cushion heel pad and toe for relief of high impact. Contents: 44 Percent Wicking Acrylic / 28 Percent Wool / 19 Percent Nylon / 2 Percent Polyester / 5 Percent Lycra Spandex / 2 Percent Silver Lining Made in the USA