Specifications:

Bluetooth Version: Bluetooth 4.1 + ERDBluetooth Profile: a2dp / HFP, HSP, AVRCP, GAVDP, AVDTPSpeaker Type: Bone conduction technology speaker, 1W dual speakersBattery: 260mAh Polymer batteryEffective Range: 10m (33feets)Receiving Sensitivity: 88dBmImpedance: 8ohmFrequency Range: 20 to 20KHzMusic Time: 8hoursTalking Time: 8hoursCharging Time: 2 hoursStandby Time: 10 daysColor: White / Black (Optional)Item Size: Approx. 13.5 * 13.3 * 5.2cm / 5.31 * 5.24 * 2.05in