Bluetooth Version: 5.0 JL6973D4 Battery inside earphone: 40mAh with Protect PCB Battery inside chargingcase: 320mAh with protect PCB Speaker: 10mm Impedance: 32ohm Frequency:20-20kHz Sensitivity: 105dB+-3dB Working time:6-7hours Standby time: 168hours LED display in charging case injection color: White or Black Closed box packing