Ring light and LED display: when switched on, the ambient light glows blue, making it easier to use in dimly lit environments in the car and creating an upbeat atmosphere. Easy and comfortable viewing of the volume, car voltage and FM frequency displayed on the LED display 2 USB ports and safe charging: supports charging of 2 devices at the same time with overload protection. One USB port (5V / 1A) with a music icon to play a USB stick and another USB charging port (5V / 2.4A) to fully charge your smart device. Enjoy in-car stereo streaming and charge your smartphone at the same time Three options for transmitting music: The Bluetooth hands-free car kit can output clear stereo music in three different ways - A. FM signal; B. SD card with support for MP3/WMA/FLAC/WAV/APE formats; C. USB memory stick (up to 32G) Hands-free calling. With this Bluetooth kit, you can easily answer/reject/redial calls with the hands-free function and enjoy safe driving. HVAC technology will dampen noise and wind, creating full duplex sound quality Easy to install: plug this wireless adapter into your cigarette lighter, tune your cars FM radio to a blank channel (87.5-108.0 MHz) and tune this FM transmitter to the same channel; pair it with your phone via Bluetooth 5.0 and voila