The Darn Tough Unstandard Stripe is 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 Seamless™ seam fusion for an ultra-smooth, invisible feel. All Darn Tough socks are made in Vermont, USA and carry a lifetime guarantee.