Using the included Jabra Link Bluetooth adapter with your Jabra device will ensure the following functionality:

Integration with computer softphone and software support with Jabra Direct
Full integration between a Jabra device and a computer softphone usually works only when combined with a Jabra Link Bluetooth adapter. Connecting to a computer without a Jabra Link Bluetooth adapter may provide audio capability in the device but not call control for answering and ending calls.
Bluetooth range
Jabra devices obtain the best possible range when they are used with a Jabra Link Bluetooth adapter and not the built-in Bluetooth in a computer. Bluetooth performance of a computer is usually limited to a range of 2-5 meters/ 6-50 feet in a typical office environment.
Factory pairing and installation
The Jabra Link Bluetooth adapter and Jabra device come pre-paired in the box. The Jabra Link Bluetooth adapter supports plug-and-play functionality, without needing to install separate software drivers on the computer.
Identification as a soundcard
When pairing with the Jabra Link Bluetooth adapter, the device is identified by the computer operating system as a soundcard and can be used for all audio purposes. If a device is paired with the built-in Bluetooth of a computer, the device is usually recognized by the computer as a headset and can only be used for communication purposes.

What is a Bluetooth adapter?