The North Face Reaxion Amp Tech T-shirt The Reaxion Amp is a classic, crew-neck cotton short sleeve t-shirt with a twist. The cotton is enhanced with FlashDry™ technology that offers enhanced moisture management and dry times when compared with regular cotton. You get a comfortable, wear-all-day t-shirt that also helps to keep you cool and dry, making it ideal for outdoor adventures and easy-going training sessions.QUICK DRYING - WICKINGQuick-drying fabric moves moisture to the surface to evaporate.