Features: 1. **Instant Heat Activation**: Our hand warmers heat up quickly, providing immediate warmth within 15-30 minutes of application, perfect for those chilly winter days. 2. **Long-lasting Warmth**: Enjoy up to 10 hours of soothing heat from each patch, ensuring your hands stay warm during outdoor activities or while working in cold environments. 3. **Easy to Use**: Simply open the package, stick the patch inside your clothing, and feel the warmth as it begins to work its magicno complicated setup required. 4. **Versatile Applications**: Ideal for winter sports, outdoor adventures, or simply keeping warm at home, these patches are also great for relieving local hand pain and discomfort. 5. **Safe and Disposable**: Made with iron powder and toner, our self-heating patches are safe for use and designed for one-time use, making them a convenient solution for winter comfort. Our hand warmers contain iron powder and toner. It can start heating immediately, the heating time is extremely short, and you can feel the warmth very quickly. Its use method is very simple: 1. After opening the package, take out the patch and stick it on the inside of the clothes. 2. The patch will start to heat up in 15-30 minutes. 3. The insulation effect can reach 10 hours. It is suitable for use when you are cold. It releases heat through a chemical reaction, raising body temperature and warming hands. Suitable for winter activities, including outdoor outing, writing heating, relieving local hand pain, etc.