Temperature regulation is the key performance indicator of any base layer, and this is especially true for a winter version. But winter poses a specific host of challenges not found in other climaCodes, namely in the form of added cold air and your additional layers. This is where our new Winter LS Skin Layer fills the gap, tuned with a thicker knit "weight," taller collar, and more stretch than our Spring/Fall version for boosted insulation and flexibility under your outer apparel. It's worth noting the Skin Layer is a total reset on our base layers of the past, wearing a completely revamped design and using a new blend of fibers. The Winter LS is roughly 13% lighter than the previous Winter Skinfoil, relying on a Circular Seamless construction that's free of irritating side seams. A winter-tuned blend of carbon and polypropylene yarns-plus elastane- are employed, which draws moisture away from your skin and insulates your core, keeping you dry, insulated, and comfortable from the outset.