Your TRUSTED base layer REBUILT for the MODERN ADVENTURE. Inside Layer: 100% ColdPruf® Technical Fiber Polyester with SILVADUR™ Intelligent Freshness Outside Layer: 70% polyester / 30% MERINO WOOL Fabric weight: 7 oz. Tailored fit sleeves and body Hidden seam comfort cuffs Drop-tail Flat seams Coldpruf Platinum II Midweight Underwear Crew Shirt - Men's