NRS HydroSkin 0.5 SS Shirt - Men's Red / Chili Red Medium 0.5 mm Terraprene neoprene with heat-reflecting titanium cuts the chill on cool days Four-way-stretch Powerspan exterior allows unrestricted movement, and the soft ThermalPlush lining feels great against your skin Paddler-specific design allows unrestricted freedom of movement and puts seams where they won't cause irritation Spandex fabric under the arms creates friction-free zones for comfortable paddling while improving ventilation where you need it most A durable water repellent (DWR) exterior coating sheds water to help reduce evaporative cooling