Smartwool Womens PhD Cycle Ultra Light Micro 3-Pack Merino^Mesh^Nylon^Spandex^Wool Made in USA Tackle the treacherous trails in this mountain bike sock from SmartWool&reg;. WOW Technology&trade; places more wool in high density impact zones to reduce shock and abrasion. SmartWool inside for moisture temperature and odor control. 1x1 welt cuff for a secure fit. Strategic mesh zones for maximum ventilation. 4&#176; fit system for all-day performance. Micro cut length for maximum ventilation. 57% Merino&reg; wool, 41% nylon, 3% elastane. Machine wash and machine dry. Sold in a 3-pair pack. Made in the USA.