2 USB Ports & Safe Charging: Supports 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 charges your smart device. Enjoy stereo streaming in the car and charge smartphones at the same time. 3 Music Playing Modes: This car Bluetooth adapter can freely stream clear stereo music in 3 ways: A. Bluetooth connection; B. USB Flash Disk(≤32GB); C. TF Card(≤32GB), supports MP3/WMA/FLAC/WAV/APE format. Hands-Free Calling: Built-in microphone with echo cancellation and noise suppression (CVC) technology, this Bluetooth car transmitter provides amazing hands-free function; Answer/reject/hang up/redial calls all in one multi-function button; Automatically switch to hands-free mode at from the music playing status when incoming calls. Blue Ambient Light: When power on, the ambient light ring lights up in blue, making it convenient to use in dark car environments and also bringing a cheerful atmosphere. Easy and comfortable to see the volume, car voltage and FM frequency displayed on the LED screen. Wide Compatibility: This FM transmitter works well with iPhone, iPad, Samsung, HTC, Sony, tablet and other Bluetooth enabled devices such as MP3, MP4 Player. It also fits all cars/trucks (12-24V).