Ski or ride longer and avoid numb, frozen feet with the Therm-ic ThermicSole Perform Heated Insoles in your boots. These anatomical insoles feature EVA foam construction for a cushy feel and heating elements that work with any Thermic SmartPack (not included). Your feet will think they're basking in the warm glow of a fire, even when you're riding the chairlift through a blizzard.