The Darn Tough No Show Tab Ultra Light is the lightest sock which gives you a lighter-than-air feel. The sock pulls moisture away from skin and repels bacteria and odor. It is made of merino wool which ensures breathability and comfort in all conditions. The sock has an undetectable seam fusion which gives ultra smooth, invisible feel. 51% Merino Wool 46% Nylon 3% Lycra® Spandex.