Duofold Men's Dri-Release Wool Mid Weight Single-Layer Thermal Tagless Bottom 100% Spandex base-layer-underwear closure 84% Polyester, 11% Merino Wool, 5% Spandex Duofold's New mid-weight was specifically designed to optimize fabric weight to warmth ratio in cold weather 360 stretch for maximum flexibility and optimum fit, excellent moisture management, quick drying and odor resistant TAGLESS for added comfort and flatlock seams to help avoid irritation Imported