Headset adapter for headsets with separate headphone / microphone plugs - 3.5mm 4 position to 2x 3 position 3.5mm M/F / cellphones 3.5mm TRRS to Mic and monitor jack Compact design for maximum portability - a great solution to have on hand in your laptop bag Lightweight, yet sturdy design that can easily be plugged in when required Headset not included Headphone/Microphone Combo Jack splitter (4-position 3.5mm to dual 3-position 3.5mm) is a headset Splitter Adapter featuring one 3.5mm Male (TRRS) and two 3.5mm (TRS) Female connectors, enabling you to add a mono microphone input, as well as a stereo output to your PC or Laptop, through a single 3.5mm audio port. It can turn the combo port into two distinct ports  one 3.5mm headphone jack and one 3.5mm microphone port. While some laptops from Apple and Dell feature only a single (4-position) 3.5mm audio port to support both audio input and output, this innovative headset splitter adapter breaks the audio port out into two distinct ports - one that can be used for a microphone input connection, and the other for connecting external (output) speakers.