Smartwool Womens PhD Outdoor Light Patterned Mid Crew Socks - Past Season 63% Merino Wool, 35% Nylon, 2% Elastane Strategically placed mesh ventilation zones provide ventilation for temperature and moisture management Flat knit durable toe seam Sock Height: Mid Crew - 5.5" overall height Knit in USA of Imported Yarn Style: SW0SW221