This is a "Y-Training Cord" that connects two headsets (Plantronics, AddaSound, or VXi - P) to a single phone to perform agent training, supervisory, coaching, multi-users on one call. A mute switch is available on the Supervisor Side. This cord allows only one user to listen/speak while the other user can only listen.
To use this cord you will need your 2 Headsets and 1 Telephone Connecting Cord (RJ9 to QD). Note: You will need to have a Telephone Adapter or Telephone Connecting Cord to connect the splitter to your phone.