The 3D Recording Headset contains a microphone in each earbud. The dual microphones enable binaural recordings, which accurately recreate the spatial audio environment. This type of recording provides the most accurate spatial sound quality because the microphones effectively mimic your ears - when you play a binaural recording back, it sounds like you are actually in the location where the sound was recorded. The jack is proprietary and will only record binaurally with Echo and Wifi pens.