Our body warmers contain iron powder and toner. It can provide lasting and stable heat. It has good thermal insulation properties and helps to retain heat. Absorbs odors and stays fresh and comfortable during use. Its use method is very simple: 1. After opening the package, take out the patch and stick it on the inside of the clothes. You can also glue it to fabric and wear it on your hand to warm your hands. 2. The patch will start in 15-30 minutes; 3. The insulation effect can last for 10 hours. Warm up quickly to keep you comfortable in cold weather. Continuous heating up to 10 hours, all-weather insulation, stable and reliable.