There are 3 sections to the MX10's compatibility:
To check if the MX10 is compatible with your telephone, please click this link and perform the appropriate compatibility check.
The MX10 audio processor uses 2 x 3.5mm audio jacks to connect to your computer via a sound card.
The MX10 is compatible with any of the Plantronics standard office range corded headsets. The only headset currently listed on that page that will not be compatible is the SupraPlus Digital headset.