HeadOn - Wirefree Headset for Phones with a 2.5mm jack 80 hrs of actual talk time, 2000 hrs of stand-by time Fully secure, ClearVoice technology - 125 channels (this is automatic) No pairing necessary, phone adapter about the size of a stamp Answer an incoming call with your voice or as you normally would Compatible with any telephone that accepts standard 2.5mm headsets. (all other phones need an adapter sold separately)