The Rechargeable Hand Warmer is a rechargeable hand warmer that can also be used as a power bank with a capacity of 10,000mAh. By pressing the Power button you can choose from 4 levels for heating between 40°C and 50°C. Light indication of the intensity of the heating setting. The Lifesystems Rechargeable Hand Warmer works reliably indoors and outdoors and the warm-up time is between 6 - 12h. Use the power bank function for all devices with 5V and 2.1A input. The warmer uses two heat plates for 360° heat radiation. The heater can be recharged using USB-C (5V, 2A max). We recommend recharging the battery at least once every 3 months to maintain battery capacity. The 4 stage heater has a 50 degree Celsius temperature so you should be careful if you have sensitive skin. Temperature as indicated by the LED: 1 LED: 40°C (+-2°C) 2 LEDs: 45°C (+-2°C) 3 LEDs: 48°C (+-2°C) 4 LEDs: 50°C (+-2°C)