1.Support A2DP, AVRCP; 2.Dual Antenna Reception System; 3.Smart connection; 4.Rechargeable battery system; 5 ... specification V2.1 version, backwards compatible with V1.1, V1.2 version ; Support automatic switching to answer phone-call ,Play,Pause ... DAC audio-outInterface Levels : 3.3V—4.2V,lithium batteryFrequency : 2.4GHz ISM bandDriver unit: : Φ30mmGFSK(Gaussian Frequency shift keying)Radiated power ...