Transmission range: 10 metersFunction: Battery display, call function, support musicBluetooth protocol: 5.0Channel: StereoHow to use : EarbudsSpeaker: high quality copper ring speakerChip: True Stereo ChipPlay time: 5 hoursCall time: 8 hoursHeadphone battery capacity: pure cobalt 55 mAhCharging box battery capacity: pure cobalt 1000 mAhEffective distance: 10+M