The main feature has been repeatedly tested more than 10 times without exception. The main and auxiliary switches, switch, pairing, and even back, the music playback is paused, the upper and lower curved, call answer, hang up, reject, etc.
The main function has been tested more than 10 times without exception. Such as primary and secondary switching, switching machine, pairing, backlink, music playback pause, up and down, call answer, hang up, rejection, etc.
The main functions have been tested for more than 10 times without abnormality. Such as main / auxiliary switch, switch on / off, pairing, connection back, music playback pause, music up / down, call answering, hanging up, rejecting, etc