Specifications:Model: M19Bluetooth Version: V5.1Bluetooth Profile: A2DP,AVRCP, HFP;HSP Working voltage: 3.1V~4.2VCharging voltage: 5V-1ABattery capacity of the headset: 50MAHBattery capacity of the storage 3000MAHTransmission Distance :10M LED Digital Power DisplayHifi Sound QualityCa..