About This Item 2 Usb Ports & Safe Charging: Supports charging 2 devices simultaneously with overcharge protection. One USB port (5V/1A) with music icon can play USB disk, another USB charging port (5V/2.4A) effectively charges your smart device. Enjoy stereo streaming in the car and charge smartphones at the same time. 3 Music Playback 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 technology (CVC), this car Bluetooth transmitter provides amazing hands-free function; Answer/reject/hang up/redial calls all in one multi-function button; Automatically switch to hands-free mode from music playing status when incoming calls. Blue Ambient Light: When powered on, the ambient light ring will turn blue , which makes it convenient to use in the dark environment of the car, and also brings 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).