Since 1935, Portuguese Flannel has been setting the bar for quality—and the Altitude Popover clears it with ease. Woven from a heavyweight cotton-poly blend, it’s warm without getting stuffy and tough enough for years of wear. The classic buffalo-check plaid keeps things rugged and timeless, while the cut makes it an easy layer to throw on when temps dip—just as ready for splitting logs out back as it is grabbing a round or two in town.