Not good sound in the earphone, it does not notify you with vibration when you remove it, it does not inform you about the low battery percentage, it has a good battery, good microphone, good fit on the neck, if you receive a call from messenger it does not accept the call by pressing the button

I have been a user of Fineblue Bluetooth for several years now, which in itself means that I am satisfied. All of its models have powerful and clear sound, and the caller always hears me correctly. I bought this particular one because it offers longer battery life. (All the others were at 6 hours, this one claims 10) I will return with impressions on the battery life at a later time.

Update.
What disappointed me on the first use is the absence of voice notification for the battery percentage upon activation, something that the other Fineblue Bluetooth had.
Also, a significant drawback is the absence of caller ID announcement, even though it only announces the caller's number during an incoming call, and even that is very slow. By the time you hear the entire number, the caller may have already hung up and you won't have time to answer.

Its battery has a longer duration than the F920 I had, but the absence of the mentioned features is more important to me.
There might be a firmware update available, but I haven't found anything.

Also, it doesn't notify you with vibration when you move away from your phone. VERY USEFUL feature that the other Fineblue headsets had! It simply says "disconnected," but if you don't have the headset in your ear, you might forget your phone somewhere.

Second update.

Its battery has nothing to do with the other Bluetooth devices of the same brand. You simply forget to charge it. It has its downsides that I mentioned above, but with such battery life, I started to like it more.

Final update.

In the end, this particular Bluetooth is only worth it for its battery. It has given me many problems in a short period of time. The latest ones are that it loses connection with the phone. While it is in use, it automatically sends the sound to the mobile phone's earpiece, and I have to go into the sound settings to restore it to Bluetooth. Other times, when someone calls me and I don't answer, it continues to give an audio signal and vibrate as if someone is calling me, even though the call has ended. It doesn't even turn off at that time, no matter how much I try to close it to make it stop, only after several attempts with the on-off button.
In short, disappointment. Huge battery, but many problems that make me go back to other models of Fineblue, like the 920, which was excellent.