See also:

Telephone
...

Maintenance
The battery is maintenance-free, i.e., the electrolyte will last for the life of the battery. Your service center will be glad to advise you on questions regarding the battery. ...

Bluetooth audio
At a glance ▷ Music files on external devices such as audio devices or mobile phones can be played back via Bluetooth. Use of a mobile phone as an audio source ▷ The sound is output ...