This crew sock keeps you comfortable throughout the day with extra durability added to high-impact areas, more than enough stretch, and improved ventilation. Made out of a combination of 63% merino wool35% nylon2% elastane. Strategically placed mesh improves ventilation for temperature and moisture management. Virtually Seamless(TM) flat knit durable toe seam. 8.5 in. tall. PhD(R) performance adds two elastics for better recovery and more stretch. 4 Degree Elite Fit System combines two elastics for better recovery and stretch. Indestructawool(TM) uses a patent-pending construction to elevate durability and comfort. Medium cushioning for impact absorption. Made in USA.