Made from Isowool™-- a superior blend of 50% Merino WOOL and 50% polypropylene. This blend is 5X's the strength and durability of Merino wool alone. Shrink-resistant and itch-free our Wool socks keep your feet drier and provide excellent insulation in all weather conditions. Our Wool socks also feature our "Easy-Fit" cuff and "Stretch-to-Fit" sizing system for maximum fit and performance.