Our foot warmer strips contain iron powder and activated carbon. It can generate heat to provide sufficient warmth for the soles of the feet or the body; It is very helpful for women with abdominal pain, low back pain and cold hands and feet during menstruation. Its use method is very simple: tear off the non-woven sticker; Put on your socks and enjoy the warmth of your feet for 6-8 hours. Easy to use, can be used for outdoor sports, in the cold season to provide you with warmth.