Style: Sleeveless Vest Material: 100% Polyester fiber Power Supply Interface: USB Power Supply: 5V/2A Mobile PowerNot Included Fever Area: Back Function: Keep warm, Anti water splashing and Prevent cold Age Of Application: Adult Men Temperature ShiftManual adjustment Warm:45 (Red Light) Comfort:35 (White Light) Energy Saving:25 (Blue Light) How To Use: 1.Take out USB plug 2.Plug in removable charger 3.Switch on the removable charger 4.Press the chest temperature control switch for two second 5.Red light flashing,means heating automatic 6.Manual adjustment has three level,red light means hign-temperature heating continuously,White light means medium heating continuously,blue light means low heating continuously 7.Press the chest temperature control switch for two second,lights out and stop heating 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. Package Included:1* Sleeveless Vest (Power Bank Not Included)