The Thermic C-Pack 1300 with Bluetooth and Heated 3D insoles is one of the best ways to warm your feet. Use the Therm-ic app to operate your battery boot heaters in your ski boots, snowboard boots, outdoor boots, shoes, and other types of footwear. The C-Pack 1300 battery pack has three manual power settings you operate with the touch of one button to determine the amount of heat you need or use the Therm-ic app which offers 10 heat setting levels. Either way, you won't have cold toes.