Choose the Glacier XT when temperatures go below those of your freezer, and you need maximum insulation! These boots wrap your feet in a thick layer of insulation, making them a reliable companion whether youre ice fishing or riding a snowmobile. In true Sorel fashion, the boots feature a removable liner that can be taken out to dry after a long day outdoors. Its hard to say whether the warmest model in our collection is the Naali by Nokian Footwear or the Glacier XT. Either way, both belong to the heavy-duty category of winter boots we can confidently recommend for extreme cold. As the Glacier XT is quite heavy, as well as spacious - Traditional handcrafted rubber shell - Waterproof textile shaft with drawstring closure at the top - Thick sole construction provides excellent insulation - 13 mm removable felt linereasy to dry - Omni-Heat lining reflects body heat back towards your feet - Additional 13 mm removable insole - AeroTrac outsole for grip US sizing.