describe:1. Fast heating: The pocket USB heater heats up in 3 seconds, then heats up in 30 seconds, and continuously cycles at 45 - 60 degrees Celsius to keep you warm. The size is ergonomically designed, allowing you to easily hold the warmth in the palm of your hand and put it in your pocket.2. Temperature display: After power on, the high temperature will display 60 and the low temperature will display 45. We are equipped with a 3000mAh lithium-ion battery with long battery life. It can be charged through battery packs, vehicle power supplies, etc., and has endurance.3. Compact and portable: The rechargeable device is small in size and heavy in weight, so it can be used in your hand without taking up too much space. Easy to carry and use, it can also be put directly into your pocket. The height of the product is approximately 99mm/3.9 inches and the width is approximately 40mm/1.6 inches.4. Gift options: Electric heaters are perfect for giving warm gifts to your dear family and friends, letting them feel warm in winter, or giving them a surprise. USB heater is an image with headphones. It is fashionable and unique, and can also be used to decorate your home.5. Soft glue: The arms on both sides of the electric motor are made of healthy soft glue. It makes you feel soft when you put it in your pocket or hold it in your hand. Rechargeable, suitable for travel, office, home, school and other scenarios. Choose a unique and attractive hand warmer to help you feel better.Specification:Project Type: ElectricMaterial: ABS, aluminum alloyBattery type: Lithium-ion battery (built-in)Battery capacity: 3000mAhHeight: approx.Width: Approx. 99 mm/3.9 inches 40 mm/1.6 inchesExtension arm size: approx. 65 mm / 2.6 inchesMaximum distance between earcups: approx. 79mm/3.1Instructions:1. Press and hold the switch of the USB hand warmer to turn on the heating function, and then click the button to switch the gear mode. There are 2 levels, 60 is the high-grade (highest calorific value), and 45 is low-grade (lowest caloric value).2. Power input interface charges the USB hand warmer through the input interface.packing list:1 x electric cable1 x charging cable