Jabra LINK 40, 14201-40 is a remote Electronic Hook Switch Control (EHS) cable provides remote answering for Jabra wireless headsets and the: 

Panasonic KX-NT553 KX-NT556 KX-DT543 KX-DT546, KX-UTG300 phones.

Jabra Link 14201-40 is compatible with:

Jabra PRO wireless headset models (Jabra Pro 920, Jabra Pro 925, Jabra Pro 9450, Jabra Pro 9460, Jabra Pro 9465, Jabra Pro 9470)

With EHS functionality,  boost productivity as they provide the user with the ability to answer and end a call, while away from their desk.