Features 1. **Long-lasting Warmth**: Our Self-Heating Hand Warmers provide up to 10 hours of continuous warmth, perfect for keeping your hands and body cozy during cold winter days and outdoor activities. 2. **Easy to Use**: Simply open the package, remove the patch, and stick it inside your clothing. Heat activation occurs within 15 to 30 minutes, making it incredibly user-friendly for anyone. 3. **Portable , Lightweight**: Designed for convenience, these hand warmers are compact and easy to carry, making them ideal for travel, outdoor adventures, or daily commutes in chilly weather. 4. **Versatile Application**: Not just for hands, these warmers can be used on the waist and abdomen, providing relief from local pain and enhancing comfort during various winter activities. 5. **Safe , Effective Materials**: Made with sodium chloride and vermiculite, our hand warmers are safe to use and provide effective heat therapy, ensuring a warm and soothing experience. Our hand warmers (2pcs) contain 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.