NEVERCOLD hand warmers are used inside the gloves as a comfortable and efficient source of additional heat. The heater can be placed inside the glove wherever you want to heat, for example, the palm or even the fingertips. If necessary, NEVERCOLD hand warmers can be used for many other purposes, such as keeping the batteries of a mobile phone, camera or other electronic device warm in the cold. NEVERCOLD hand warmers are small pillow-shaped bags made of a porous material with a mixture of vermiculite, iron powder, wood powder, activated carbon and salt inside. When the sales package surrounding the bag is opened, the mixture is allowed to react with air, causing heat to begin to form. The reaction continues on its own for 10 hours. The production of heat can be interrupted by moving the bag to an oxygen-free place, e.g. an airtight minigrip bag, so that the use of the heater can be continued later.