Ultrafine microfibers create a cocoon of warm air. Incredibly soft. Lightweight, dry and breathable. Half-zip front. Its a marvel of technology that a sweater this light can keep you so warm. Very fine microfibers (finer than silk) produce a weave that wont let your body heat dissipate. Instead a cocoon of warm air is created around your body to protect you from the bitter cold. These ultrafine fibers also produce a fabric that is incredibly soft, lightweight, dry and breathable. Classic half-zip sweater offers both style and comfort. Washable. Imported. Sizes: Small-3XL. Add $5 for sizes 2XL and 3XL.