This Electronic Hook Switch (EHS) adaptor lets you remotely answer and end calls away from your desk using the multifunction buttons your wireless headset ear piece.

It is designed to work with the following Jabra wireless headsets:  Jabra PRO 920, Jabra PRO 9450, Jabra PRO 9460Mon, Jabra PRO 9460Duo, Jabra PRO 9465Duo, Jabra PRO 9470, Jabra 9350e, Jabra 9330e, Jabra 9120 and Jabra 9125.

It is compatible with the following Avaya telephone models:  2420 version B on IP switch only / 2420 IP Ver Firmware> 4.0  /  4610 & 4610SW Firmware> 1.8  /  4620 & 4620SW Firmware> 1.8  /  4621 & 4621SW Firmware> 1.8  /  4622 & 4622SW Firmware> 1.8   /  4625 & 4625SW Firmware> 1.8  /  4630 & 4630SW Firmware> 1.8  /  5620  /  5621  /  5625.