Pull On closure Premium Bamboo Material: 82.2% Rayon from Bamboo, 15.6% Polyester, 1.3% Spandex, 0.9% Elastic. Fabric made from bamboo is extremely soft. People who cannot wear hemp or wool directly on their skin because of uncomfort will experience no irritations from bamboo. Widely considered as a more renewable source than cotton. Smell Control & Moisture Wicking: Bamboo evaporates 3-4 times more moisture than cotton and prevents feet from sweating. Bamboo fiber has a hollow structure which makes them super-absorbent and breathable, which keeps sweaty smelly feet feeling fresh for longer. Cushioned Sole & Control-Slip: Extra cushioned sole provides the perfect support, absorbs impact to protect your arch and ankle. Reinforced heel makes sure the +MD bamboo no show socks stay in place. For Everyday Wear: Whether you’re tackling the workday, exercising, or lounging at home, our socks will provide the ultimate comfort. Thermo-regulating keeps your feet cool during the warm months and maintain the heat during the cold days. Longlasting: Bamboo fiber will be much softer after the first wash. We recommend you wash them before you wear them. After washing, the socks will shrink slightly, but will regain their original size and shape after you put them on.