The North Face's Summit Series prepares us for anything in the alpine, and the Summit Breithorn Pant is no exception. With its lofty 800-fill ProDown insulation, these midlayer pants provide impeccable warmth while we explore at high elevations. Full-length side zips make it easy to take these pants on and off. Unlike other insulators, these pants don't carry excessive bulk, and the articulated knees let us move around comfortably while we're bundled up.