FM Transmitter.Play stereo quality sound from your phone、 Micro SD card、 USB flash drive and MP3 to your car speaker stereo system via FM radio signals. Tune your car's radio into any unused FM channel and match the same frequency on PN38P from 87.5MHz to 108.0 MHz.In-car Speakerphone.It's an excellent hands-free solution after Bluetooth connection、 talk freely on your mobile phone、 with your eyes on the road and your hands on the wheel. Just press the big friendly button to answer and enjoy crystal clear hands-free conversation.Stream Music.AUX audio input allows you enjoy music without adjustable frequency. 3.5mm audio cable can stream music from non-Bluetooth enabled devices like MP3 player. Features memory for your last set frequency、 play music files in the MP3 or WMA format on an Micro SD card or USB flash drive.Smart Car Charger.USB port on the plug supplies a current of up to 2.1A to charge all the phones and tablets. Advanced Technology: Echo cancellation and noise suppression (CVC) technology、 LCD screen shows the voltage of car battery in real time