Uncompromising on warmth, Korkers Polar Vortex 1,200 Boots are built for comfort and safety in extreme cold. The kind of cold weather that makes headlines. 1,200-gram Thinsulate Insulation is here to protect you and keep you warm while snowmobiling, ice fishing, checking utility lines-or whatever calls you into sub-zero frigid air. Plus, Thermal Stack underfoot insulation and an aerogel frost barrier insole are rated for extreme cold. Since keeping dry is critical in cold weather, a 100% waterproof breathable bootie is combined with waterproof leather to keep feet bone dry. Dial-in your fit with the BOA closure. No more removing your gloves to tie your laces. The BOA Fit System uses cables to secure your foot with micro-adjustment precision. Simply press the dial and give it a turn to comfortably tighten the grip exactly where you want it. It stays locked-in throughout the day. And when you want to loosen or take off the Boots, pull the dial for a quick release. 100% breathable, waterproof membrane keeps you dry Waterproof leather, webbing, and stitching keep out snow and slush 1,200 gram Thinsulate Insulation, plus Thermal Stack for warmth in extreme cold, even underfoot OmniTrax 3.0 Interchangeable Sole System for customized traction on the fly Includes TrailTrac outsole with high-friction rubber lugs Compatible with additional outsoles Aerogel frost barrier insole gives you additional underfoot warmth BOA M4 Fit System for easy, one-hand micro-adjustable inchlacing inch Protected stitching around toe and heel for abrasion resistance Molded TPU toe cap protects from walking hazards beneath the snow EVA midsole cushions while adding further distance from cold surfaces