This clever adapter cable allows you to plug the Espresso Portable Phantom Power Supply and your earbuds straight into your SmartPhone! Now you can record with most high-quality microphones directly into your phone, and easily monitor your recordings too. At one end is the familiar male TRRS 3.5mm plug that goes into your SmartPhone. Out of that comes two cables: one terminates in a 1/4″ TRS balanced phone jack to plug into the Espresso Phantom Power Supply; the other is a 3.5mm TRS stereo female to receive your earbud plug. Some apps may enable you to monitor the recorded signal live with the earbuds; others will only permit monitoring upon playback.