The key to temperature control in cold weather is sweat management. The Chrono LS Base Layer with proprietary Wikpro material keeps you warm, dry and comfortable in the coldest conditions. Wikpro is a proprietary blend of polyester and nylon that improves moisture management while remaining comfortable to wear. This is the same fabric used in the popular Chrono SL Base Layer undershirt, but in a heavier quality for extra insulation. This first layer is the basis for a comfortable ride in cool temperatures.