The Jabra Link 14201-43 EHS Adapter is designed for Jabra wireless headsets and specific Cisco Unified IP Phones, including the 6945, 78xx series, 79xx series (like 7942G, 7945G), and 88xx series (like 8811, 8841, 8845, 8851, 8861, 8865). It enables remote call control (answer/end calls, volume, mute) directly from the headset by converting signals between the phone and headset, but requires correct setup on the phone and ensuring your specific headset model (like Jabra Pro 900/9400, Engage 65/75) is compatible.