Warm enough to handle the coldest conditions on Earth, the Sorel Women's Glacier XT Boot is a necessity for mid-winter glacier treks, Antarctic expeditions, or just daily life above the Arctic Circle. The thick ThermoPlus felt liner and Meltdown midsole keep your feet toasty, and the Omni-Heat lining reflects your heat back to your feet for an extra dose of warmth. A rubber shell and PU-coated upper shrug off snow and slush, and the Aero-Trac rubber outsole helps you keep your footing on icy surfaces.