"Weather Rating: EXTREME COLD The world's warmest, lightest thermal product. Patented fabric technology provides maximum warmth without excessive weight or bulk. Super soft fleecing provides all day comfort. 100% fleeced acrylic inside, 50% Polyester/50% Cotton outside. Reinforced flat seam construction for smooth fit and extra strength. Long Sleeve Shirts with Extended Tail, Ankle Length Drawers and Union Suits."