M19 TWS Wireless Bluetooth Earbuds Earphones Touch ControlModel : M19Model: M19Bluetooth specification:V5.1Bluetooth Profile:A2DP,AVRCP, HFP;HSPWorking voltage:3.1V~4.2VCharging voltage:5V-1ABattery capacity of the headset: 50MAHBattery capacity of the storage box:2000MAHPower Bank OptionTransmissio..