Inside the chip Barrot br8041a01 is installed, the version of Bluetooth v5.0, but in general the device does not work very well. Communication range 2-3 meters. Transmission rate 77kb/s. For example, my old Buro BT-40 (v4.0) gives a speed of 167kb/s.
In Windows 10 drivers are installed automatically, two headsets are connected simultaneously, but I worked with interruptions.
For Windows 7 there are no native drivers, suitable from csr8510, but are defined as v.4.0
The old headset Jabra bt2080 did not connect.
I would rather add money and buy a better device.