specification:    Bluetooth Version：V2.1 EDR   Frequency coverage: 2.402~2.480 GHz ISM Band   Sensiticity: -80dbm   Wireless transmitter standard: Class 2    Channel: 79 channels of 1MHz BW  Contact terms: Point-to Point   Transmit range: Up to 10m   Transmit speed: 57~723Kbps   Stereo compression

specification:    Bluetooth Version：V2.1 EDR   Frequency coverage: 2.402~2.480 GHz ISM Band   Sensiticity: -80dbm   Wireless transmitter standard: Class 2    Channel: 79 channels of 1MHz BW  Contact terms: Point-to Point   Transmit range: Up to 10m   Transmit speed: 57~723Kbps   Stereo compression ratio： 44.1/48 KHZ    Support format: MP3 WAM    Talk time:Up to 4H    Charge time:1-2H