Brooks Run-In Three Pack 3 Pack Socks (Large US Women 10-12.5 / US Men 9-11.5, Nightlife/Black/White) 96% nylon / 4% spandex DriLayer quick-drying yarn Double-tab design: Achilles tab prevents sock from slipping and front tab provides protection from shoe tongue irritation Mesh zone at upper foot for decreased weight and added ventilation Midfoot compression