Features: 1. **Long-Lasting Warmth**: Each hand warmer provides up to 10 hours of soothing heat, perfect for keeping you warm during cold winter days and outdoor activities. 2. **Easy to Use**: Simply open the package, remove the patch, and stick it inside your clothing. It starts heating within 15-30 minutes for instant comfort. 3. **Portable & Convenient**: Lightweight and compact, these hand warmers are easy to carry in your pocket or bag, making them ideal for travel, sports, and outdoor adventures. 4. **Versatile Applications**: Perfect for various winter activities such as hiking, skiing, or simply keeping your hands warm while writing or working outdoors. 5. **Safe & Effective**: Made with sodium chloride and vermiculite, our hand warmers are safe to use and provide effective heat therapy for local pain relief and comfort. Our hand warmer (20pcs) contains sodium chloride and vermiculite. It can release heat, raise body temperature and warm hands. Its usage method is very simple: 1. After opening the package, take out the patch and stick it inside the clothes. The patch will start heating within 15 to 30 minutes. The heat preservation effect can last for 10 hours. And it can be applied to winter activities, including outdoor outings, writing warm handwriting, local pain relief, etc.