Featuring a women's specific design, the SmartWool Women's PhD Outdoor Medium Pattern Crew Socks stay in place and offers a light cushion for all-day performance. The padded Achilles tab offers additional protection. ReliaWool Technology in the heel and toe adds more durability than ever before. Features: Strategically placed mesh ventilation zones provide ventilation for temperature and moisture management Flat knit durable toe seam 7.5" overall height Sock Height: Crew Machine washable Knit in USA of Imported Yarn: 63% Merino Wool/35% Nylon/2% Elastane Women's Sizing (Shoe Size Reference): S: 4-6.5 M: 7-9.5 L: 10-12.5 XL: N/A