The new cut and fabric of the Siren Long Sleeve Sweetheart make it even more comfortable. It's made with corespun fabric, made from nylon fibers wrapped in merino wool, for durability and strength, while being soft against the skin. Perfect to wear all year round, when traveling, hiking or relaxing after a day outdoors. The flattering classic V-neck and cut of the Le Siren Long Sleeve Sweetheart are perfect for everyday comfort and easy layering.