From SmartWool, these socks feature: Crew silhouette Light cushion Indestructawool™ technology with extended durability zones 4 Degree™ elite fit system for a dialed-in, performance-oriented fit Additional body-mapped mesh zones for added breathability Virtually Seamless™ toe for enhanced comfort Comfort welt with 'stay put' fit Merino wool/nylon/recycled nylon/elastane One size fits men's shoe sizes 9-13 Machine wash/tumble dry Made in the USA.