Key Specifications: 1. Bluetooth Version:2.0 2. Bluetooth Profile Version: Headset Profile, Hands free Profile and Advanced Audio Distribution Profile(A2DP) 3. Transmitting Power: Class 2 4. Working Distance Range: 10M 5. Frequency Range: 2.4026GHz -2.480GHz 6. Rechargeable Battery: Lithium polymer, 550mAh 7. Output Voltage:5.0V(type350mA) 8. Charge Time: 3.5-4 hours ; Talk Time: 14 hours 9. Listen Time: 12 hours ; Standby Time: Up to 200 hours 10. Headset Size(Folded): 128.3(L) x 73.2(W) x 38(Thickness)mm 11. Weight(main unit): 67.8g