You won't think twice about going for an extra mile or ride with the Marmot Women's Polartec Baselayer ½-Zip Jacket. It's constructed with midweight fabric for extra warmth under your gear, plus flatlock seams that enhance comfort. Get some air après ski thanks to its half-zip style. Thumbholes keep your hands covered and layering easy, while the tag-free neckline reduces irritation. Unlike other women's pullovers or workout jackets, it offers built-in UPF 50 that provides extra protection from the sun.