Nevercold Toe warmers are handy extra warmth bags that you can use to keep your feet extra warm during winter frosts. Thanks to their adhesive surface, it is easy to make the heating pads stay in place between the sock and the sole of the shoe. Excellent additional warmth for winter activities. Toe warmers are small pillow-like bags made of porous material, with a mixture of iron powder, activated carbon and salt inside. When the sales package surrounding the bag is opened, the mixture can react with the air, causing heat to form. The reaction continues on its own for 9 hours. The production of heat can be stopped by moving the bag to an oxygen-free place, e.g. into an airtight minigrip bag, so you can continue using the heater later. Features: Activated by air when the package is opened Reaches operating temperature in about 5 minutes Operating time 9 hours Average temperature 36 °C Two heaters in the package