Devil’s Thumb isn’t the tallest peak in Alaska’s Boundary Range, but its vertical crags and crevasse-laced ice fields more than live up to its name. Conditions like these demand a brawnier base layer with the extreme abrasion resistance and mobility for real work. And that’s exactly what you get with Boundary Range Base Layers. The 6.8-oz. 93% polyester/7% spandex knit has 4-way flex for unrestrained action and wicks sweat from skin to head off hypothermia. Nylon reinforcements at shoulders, elbows and knees withstand treatment that shreds standard base layers, and flat-lock seams guarantee smooth going. Close-fitting Pullover Hoodie features a warm drop tail, zippered chest pocket and thumbhole sleeves. Suit up and climb all over your workday.