Exclusive to Patagonia, this Polartec Power Grid fabric with Polygiene permanent odor control is light and breathable with outstanding stretch and durability. Off-shoulder seams sit comfortably under pack straps. Pullover silhouette has deep center-front zipper with a soft kissing-welt zipper garage at chin for next-to-skin comfort. One left-chest pocket has slim zip install, zipper garage and mesh pocket bag. Cuffs and hem finished with ultrasoft binding to seal in warmth.