The MT202-EXE comes with dual USB and telephone interfaces.  It connects to your computer for any session using VoIP applications, such as Skype For Business or Zoom.  It connects via the headset jack to any telephone system such as PSTN (analog), digital, IP, and cellular phones.  It has bridging capabilities to allow one three-way call between two separate interface conversations.  This device has unlimited daisy chaining ability allowing the linking of multiple Duets to accommodate larger rooms, this broadening the Duet Executive's range of use from a desktop solution to a medium conference room solution.