(-) If the sound source is too high, the transmitter saturates (bass & treble) and if you set the source volume to avoid this, the loudness broadcast by the radio is very (very) low which strength to put up the volume on the car stereo, which makes also saturate your speakers (and if you have the misfortune to change stations .. Beware ears!).
(+) And microUSB car charger cable provided, it is something gained.
In short, a product that works in theory but in practice almost unusable.
Tested with Samsung smartphone (2013) and Renault car radio (1998).