Merino wool is the original high-performance fiber. Merino wool is moisture-wicking, breathable, quick-drying, antimicrobial, stain resistant, water repellent, static resistant and durable. The Smartwool NTS Mid 250 Crew Base Layer Shirt incorporates all of these features into a base layer that is designed for mid to late season hunting. The NTS Mid 250 Crew Shirt also features a form fit and flatlock seam construction, for the best fitting, most comfortable next to skin shirt available. This shirt is so comfortable and high-performing you'll wonder what took you so long to find it.