The Daehlie MOUNTAIN WOOL LONG SLEEVE is a wool blend base layer that is ideal for year-round, moderately intense training. It's great for cold days because you get all the properties that wool provides thanks to the durable blend of merino wool and Tencelâ„¢. It absorbs large amounts of moisture while maintaining its breathability. The T-shirt regulates your body temperature because it insulates well when it's cold and cools quickly when it's hot. Tencelâ„¢ enhances the natural sweat wicking properties of wool. Flat seams and seamless shoulders are comfortable and reduce the possibility of chafing.