Stereo Splitter -2.5mm TRRS 4 Pole Plug to 3.5mm MIC [microphone] & Headset Earphone Jack Adapter. 4-position 2.5mm to dual 3-position 3.5mm headset splitter adapter features one 2.5mm male plug and two 3.5mm female connectors, allowing 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.
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