Women's Smartwool Phd Outdoor Medium Crew - Black - Socks Graduate to superior sock wear with the PhD Outdoor Medium Crew. Sold as a one-pair pack. Crew-cut style sits at the calf. Self-adjusting welt cuff. Medium cushioning provides impact protection and ultimate comfort on the trail. Ribbed cuff. 4 Degree Elite Fit System uses two elastics for improved stretch and recovery. Patented ReliaWool technology in high impact areas provides superior durability Virtually Seamless toe for extraordinary comfort in any trail shoe. Mesh vents keep feet cool and dry. Flat knit durable toe seam. 65% wool, 33% nylon, 2% elastane. Machine wash cold, tumble dry low.