PowerDry- features two different yarns on either side of the fabric to move moisture away from the skin quickly. This soft, stretchy fabric isn't just the best technical lining of the outdoor market it is ideal for underneath helmets or for the very active.  It outperforms all next-to-skin fabrics on the market because its patented construction has two unique surfaces: the soft inner layer rapidly wicks perspiration away from the body, while the durable outer layer spreads moisture for maximum evaporation.