NRS HydroSkin 1.5 LS Shirt - Men's 1.5 mm Terraprene neoprene with heat-reflecting titanium provides substantial warmth without sacrificing comfort or mobility VaporLoft fleece lining adds warmth, dries in a flash and feels great against the skin Four-way-stretch PowerSpan exterior stretches with your movements for unrestricted paddling Paddler-specific design puts seams where they won't cause irritation Side zipper that opens from the bottom of the shirt eases put on and take off