Features: *1. Many Heating Zones and 3 Temperature Adjustments:carbon fiber heating elements generate heat across the waist, belly and upper back; One button for 3 heating settings. *2. USB Charging: Easy to charge. You need to always connect 5V2A mobile power (this product does not include mobile power). The mobile power needs to be removed during washing. *3. Safe and Healthy: Only 5V far infrared heating, far below the human body safety voltage 36V. Stable heat and body safety voltage. Suitable for better warming of the abdomen and waist area. *4. Large-area Heating: The electric heating vest has Many built-in heaters, which have a blood circulation and warmth function, which not only warms your stomach, back, waist and abdomen, but also promotes blood circulation. *5. Wide range of applications: This heated vest is ideal for outdoor skiing, winter fishing, mountain biking, cycling, camping, snow hiking, hunting, outdoor attendance, winter street, daily office, etc. *6. Safe and lightweight: the upgraded heating system can ensure you to enjoy comfortable warmth. Large area carbon fiber wire heater is safe and insulated. Comfortable & skin-friendly, touching smoothly and warmth better. It can help you spend the whole winter easily without wearing big clothes in cold conditions. Instructions: (1).Take out the USB plug. (2).Access to the mobile charging power source (3).Press and hold the chest temperature control output switch for 3 seconds. (4).Long press the chest temperature control switch for 3 seconds, start to warm up and then adjust to the medium temperature heat when you need to always connect the mobile power. (5).Manual adjustment to the third gear, warm temperature of 45 degrees Celsius, comfortable gear temperature of 35 degrees Celsius, energy-saving gear temperature of 25 degrees Celsius. (6).Press and hold the chest temperature control switch for 3 seconds, and turn off the light to stop heating. How to Clean the Heating Vests： Machine wash & hand wash are available. Do not wring or twists. Unplug the powers before washing and make sure it is dried before heating. Specification： Size: M/L/XL/XXL/3XL/4XL/5XL Product name: Heated Jacket Material: Polyester fiber (polyester) Features: intelligent three-speed temperature control adjustable Package List: 1 * Heated Jacket(not include power bank)