EarphoneModel: ETI81Charging case model: ETI82Audio qualityDriver: 8 mm dynamic driverDriver sensitivity: 100.6 dB @ 1 kHzFrequency response range: 20 Hz - 20 kHzBluetoothBluetooth codec: AAC/SBCBluetooth version: 5.2Bluetooth range: 10 mBattery LifeBattery type: Rechargeable Li-ion CellBattery capacity: 40 mAh (Earbuds) / 400 mAh (Charging Case)Music play time (50% volume): 6 h (single charge)/ 24 h (with Charging Case)Communication time (50% volume): 4 h (single charge)/ 15 h (with Charging Case)ChargingCharging time: 120 min (Earbuds)/ 150 min (Earbuds +Charging Case)Charging port: USB Type-CThe above specifications were obtained based on tests performed in OPPO laboratories.Charging times were tested in OPPO laboratories at a temperature of 25C using an OPPOstandard charger. The actual results may differ slightly depending on environmental factors andthe charger used.Water and dust resistanceDust & water resistance (Earbuds): IP54SizeWeight: 4.0 g/Earbud37.0 g/Charging Case, 45.0 g/HeadphonesSize (Charging Case): 67.0 mm*40.4 mm*27.2 mmSize (Earbud): 22.2 mm*19.6 mm*22.7 mmSize (Package): 120 mm*120 mm*36 mm