Plantronics-EHS Cable APP-51 (Polycom)
The first cable didn't work, I called Plantronics and everyone there was very kind and helpful. They overnighted the second cable and it works perfectly. The quality of sound is crystal clear. Also, I love that I don't have to add a hand receiver lift and can choose to answer my phone either by using the headset or picking up the receiver itself. I've recommended Plantronics headset & the EHS cable to our regional manager.