Car charger FM digital display Double USB 3.4A Black. This charger is compatible with bluetooth, a USB key, an SD memory card while charging your devices. You can make your calls safely while driving. After a first connection, the charger once turned on automatically adjusts the sound, the FM station chosen or the last song listened to (thanks to its memory function)... You can therefore listen to your own music thanks to the various features of the product. You just need to place the product in the cigarette lighter of your car, a radio station has been given to you by the device, then you just have to choose it on your car radio (you may have to change the radio station because it is unavailable), activate your bluetooth and connect the device to your phone. You can thus trigger your playlist. You can play/pause; hang up/answer a call with a short press on the central button, adjust the volume by turning the main button, go to the next or previous song using the various buttons.