The Marmot Women's Aeolian LS Shirt is a light trail button up shirt for comfort in warm weather. Using AirExchange fabric, a 100%; polyester Aeolian plain weave, it increases airflow so your Upper half can breathe easy during the High mile days. The hem has a drop tail with split seam, making it comfortable whether you're wearing a pack or not. Features of the Marmot Women's Aeolian Long Sleeve Shirt Air exchange Performance fabric for air permeability Packable, air permeable, lightweight fabric Ultraviolet protection factor (UPF) 20 Durable flat-felled seams Darts for tailored Fit Double chest pockets Shirt tail hem with drop tail back with split seam Fabric Details 100% Polyester air exchange plain weave 2.5 oz/yd