Note: We recommend using 5V / 2A at Ensure a good heating effect Instructions: 1. Check the USB socket 2. Access to the treasury 3. Adapter on the switch for charging the external battery 4. Humidity temperature sensor on the humidity temperature sensor for 2 seconds Lnstructions: (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. (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. Warm Tips: 1.If not used for a long time,please do not plug in removable charger 2.Do not use high temperature water or strong acid detergent. 3.Forbidden to use electricity for wet clothes,Please turn off the power and stop using if cloth is wet. 4.Use time depending on the capacity of removable charge. Washing instructions: 1.Take out removable charger. 2.Neutral detergent is available and then hand wash. 3.Do not force knead or beat. 4.After nature air drying can be use. Please kindly note that our sizes are Chinese sizes, which are usually smaller than US & Europe sizes. Please choose your size according to size chart and we suggest one or two sizes bigger to match US & EU size