Bluetooth scheme: JL, V5.4Supported protocols: HFP, A2DP, HID, AVRCP, AVCTP, AVDTPBattery capacity of earbuds: 28mAh*2 (No protection board but protection IC) battery: 200mAh (protection board)Charging voltage: DC5VCharging time: 1hPlay time: 5hTalk time: 4hStandby time: 300hBest call distance<1mMaximum transmission distance: 10mVoice prompt: supportImpedance: 32ΩSensitivity: 112±3dBFrequency response range: 2.402GHz to 2.480GHzHorn: φ13mmMulti-point connection: unsupportedWearing method: in-earUser manual: Chinese and EnglishCharging port: Type-CAccessories: USB charging cable, user manual