Please feel free to contact us if you have any questions about our products and service.Hope you can give us a five-stars feedback if you are satisfied with our products and service.Specifications:Drivers: 57mm speaker X 2Transducer type: dynamicBluetooth version: V4.1Frequency range: 2.4GHz-2.48GHzOperating distance: up to 10m (free space)Bluetooth profiles: A2DP��AVRCP��HSP��HFPImpedance: 16��Frequency response: 20Hz-20kHzSensitivity: 110dBDistortion:<0.1%(THD)Music playtime: up to 40 hoursTalk time: up to 45 hoursStandby time: up to 1625 hoursCharging time: about 2 hoursOperational temperature: -10 to 50��CColor: Black， White Red， Blue(Optional)Main item size: 17.5 * 17.0 * 8.0 cm / 6.88 * 6.69 * 3.14inMain item weight: 193g / 6.8ozPackage size: 21.5 * 20.5. * 8.5 cm / 8. 46 * 8.07 * 3.34 inPackage weight: 428g / 15.09ozPackage List:1 * Bluedio Bluetooth Headset1 * Audio Cable1 * USB Cable 1 * (Chinese， English， French， Spanish， Japanese， German) User Manual