Darn Tough donates 5% of the sales of the ATC Appalachian Trail Conservancy Micro Crew Socks to help support the ATC's outdoor educational programs and maintenance of America's first national scenic trail. Made from soft merino wool, nylon and Lycra spandex in a high density knit for Darn Tough durability and blister free bliss. Custom shrink treated merino wool regulates temperature, manages moisture, naturally resists odor, and does not itch. High density cushioning on foot bottom for comfort and performance wont flatten out under pressure. Ring toe construction for a comfortable, invisible seam. Reinforced heel and toe for abrasion resistance and miles of durability. Knit in elastic arch support for precision fit and increased endurance. Form fitting toe box and sculpted heel pocket enhance fit. Noncushioned leg, wide ribbed, 34 crew height. Darn Tough socks are made in Vermont. Machine wash warm inside out, gentle cycle tumble dry low.