The Darn Tough Unstandard Stripeis a no slipping, no bunching sock. The design displays a splash of style features the lightest wearing yarn. This sock features unprecedented durability and is naturally antimicrobial. The fast action wicking pulls moisture away, featuring Merino Wool which is the ultimate fiber for breathability and comfort in all conditions. It is made of 53% merino wool, 44% nylon and 3% Lycra spandex, featuring True Seamlessseam fusion for an ultra-smooth, invisible feel. All Darn Tough socks are made in Vermont, USA and carry a lifetime guarantee.