2 USB PORTS SAFE CHARGINGSupports charging 2 devices simultaneously with overcharge protection. One USB port(5V/1A) with music icon can read USB disk, another USB charging port(5V/2.4A) efficiently gets your smart device fully charged. Enjoy in-car stereo streaming and charge smart phones at the same time. 3 MUSIC PLAY MODESThis FM transmitter for car can stream clear stereo music freely in 3 ways--A. Bluetooth Connection; B. USB Flash Disk (32G); C. TF Card (32G), Supports MP3/WMA/FLAC/WAV/APE format. AMBIENT BLUE RING LIGHTWhen power on, the ambient luminous ring light will illuminate blue, making it easy to use in car dark environments, and also brings a cheerful atmosphere; Easy and comfortable to view volume, car voltage and FM frequency displayed on the LED screen. HANDS-FREE CALLSBuilt-in microphone with echo cancellation and noise suppression (CVC) technology, this Bluetooth FM transmitter provides an amazing hands-free function; Answer/Reject/Hand up/Redial calls all in one multifunction button; Automatically switch to hands-free mode from music playing status when coming calls. WIDE COMPATIBLITYThis Bluetooth transmitter is well compatible with iPhone, iPad, Samsung, HTC, Sony, Tablet and other Bluetooth enabled devices such as MP3, MP4 Player. Also it will fit all cars/trucks (12-24V).