The Boulder Medium Weight is a medium-weight traditional hiking sock, ideal for colder temperatures. It features our outer plaiting construction, which surrounds the softer body yarns with more durable stretch yarns for better insulation and improved longevity. Top-to-toe full-density padding cushions the instep and calf when wearing heavy boots, and 100% US-grown merino wool provides exceptional insulation, even when wet with snow or perspiration. U.S. Merino Wool Merino wool is soft, itch-free, naturally odor- and bacteria-resistant, cool in the summer and warm in winter. We source our 100% U.S. grown merino wool exclusively from sheep raised by American farmers on American farms. Full Cushion High-density cushion from top to toe for all day performance. CREW Traditional sock height that fits firmly on the lower calf, also known as the daily. Seamless Toe Closure Advanced knitting techniques create a totally flat connection in the toe box, reducing bulk and eliminating blister-generating friction. Durability Assured Reinforced construction and low-stress seam placement reduce wear and tear, increasing the life of the sock. Ingredients 71% U.S. Merino Wool 28% U.S. Nylon 1% U.S. Spandex