This device lets you stream music and calls directly from your Bluetooth device to your car FM stereo system. Multifunction: constructing with FM transmitter, hands free talking, FM radio, car charger and FM displayer. Wider Range: full FM radio frequency ranges from 87.5 to 108.0MHz, you will get a frequency without interference more easily and do not have to keep re-tuning it. Dual USB Ports: One is designed for transmitting and reading the MP3 files automatically Multi Protection: overcurrent protection, over-voltage protection, short circuit protection, overpower protection Memory Function: automatically connect to its memorized paired Bluetooth device when power on.