Works with any sound card and most telephone handsets.
Two 3.5mm plugs go into the Mic and Speaker/Headphone Jacks on a PC or Laptop Sound Card.
Works great with Skype or VoIP Softphones.
Mono output from the handset transmitter to both L & R channels (a handset will always be mono).
Works with most handsets and telephone headsets with a modular plug... It must have an electret transmitter (mic) that's normal polarity (not reversed polarity), if you don't have a handset already, we have hundreds of types, ask us for a recommendation.
This version comes with 1' cords to make it easier to travel with. We also have a Desktop version (#DSI9H) that comes with 6' cords.