- Real-time temperature display: The hand warmer features a high precision LED indicator that shows the current surface temperature in real time, enabling you to monitor heat levels and avoid overheating or underheating for the most comfortable warmth. - Comprehensive safety protections: This rechargeable hand warmer integrates overcharge protection, short circuit protection, overheating protection, surge protection, and power protection. If any abnormal condition is detected, protective measures activate immediately to ensure safe use. - Three temperature settings with long runtime: Choose from 40 C (104 F), 50 C (122 F), or 60 C (140 F). Runtime is up to 18 hours or more at 40 C, at least 13 hours at 50 C, and at least 8 hours at 60 C, supporting extended outdoor activity or indoor warmth. - Compact and portable design: Exquisitely compact and lightweight, easy to hold and carry. Fits in a pocket, purse, or on a desk without taking up space, making it a convenient companion for winter travel, office, study, or home relaxation. - Practical use scenarios: Ideal for outdoor activities in cold weather such as skiing, hiking, or camping; suitable for long desk or study sessions at the office; convenient for travel, commuting, or bedside warmth at home.