20232893 Filson Men's Mackinaw Jac Shirt As much a jacket as it is a heavy shirt, this updated Mackinaw Wool Jac-Shirt is warm, weather-resistant, and highly breathable. For even more warmth, it's lined with Filson's signature Alaskan Guide Flannel that's been a favorite of bush pilots, sportsman and tradesmen for decades. Built with virgin Mackinaw Wool Lined with Alaskan Guide flannel in the torso Lined with polyester twill in the sleeves Front closure and adjustable cuffs secure with snaps Angled-entry flannel-lined hand pockets Snap-flap chest pockets; left side with additional slotted utility pocket Fit Relaxed fit allows room for midweight layers underneath Fabric 26 oz | 100% Virgin Mackinaw Wool Lining: 8 oz | 100% Cotton Flannel & Polyester Twill Product Care Dry clean only