Specification Driver unit :40MM Impedance :32 ohm Sensitivity : 95db AT 1KHZ Frequency response :20-20khz BT version: V5.0 JL Charging case capacity: 300MAH Playing time : about 9-10H Charging time : about 2.5H Stand by time : about ?H Wireless transmission distance :10m Noise cancelling :18+/-3dB