Features:Model: OWS902Bluetooth Version: V5.3Speaker Size: Φ8mmEarbuds battery: 40mah, Charging Case: 300mahSpeaker Frequency: 20Hz～20KHz, Sensitivity: 102±3dB 1kHzSpecifications:Model: OWS902Frequency :20Hz_20KhzImpedance :7Ω ±15％ at 1000HzSound level/Sensitivity :Input Power 50mW Sine Wave Input 4.2V， Must Be NormalConnection Type :BluetoothMicrophone :YesBattery :Charging Case Battery: 3.7V/400mAhEarbuds Battery: 3.7V/50mAhDuration :Rated output power: Rated Power Input 50mW Music Playtime: 6H（60% Vol）Call time: 4H Standby time: 200HCharge time: 2HAppearance may slightly different than picture