A soft and stretchy top for daily comfort, the Merino 150 Siren Long Sleeve Shirt with Sweetheart Neckline is made from icebreaker's Corespun jersey, which is durable and feels silky-soft against the skin. The Siren is perfect for year-round wear, whether traveling, hiking, or simply relaxing. It also features a flattering neckline and a slim fit. Inspired by nature, icebreaker utilizes the functional properties of natural fibers to provide an alternative to synthetic clothing. Merino wool is an annually renewable fiber that naturally resists odor. It cools in heat and warms in cold, allows the skin to breathe, and ensures lasting comfort. Corespun Merino - a merino blend that regulates body climate in all weather conditions. A soft and stretchy base layer for daily comfort and easy layering, the Merino 150 Siren Long Sleeve Shirt with Sweetheart Neckline is characterized by a snug fit and our Corespun merino blend. 83% merino wool, 12% nylon, 5% elastane. Wash in a warm wash cycle in the washing machine. Wash inside out with similar colors. Do not use fabric softener. Do not bleach. Do not tumble dry. Hang to dry in the shade. Do not iron hot. Do not iron prints and accessories. Do not dry clean.