MEIDI SMART BLUETOOTH FM TRANSMITTER is an easy to use, convenient product that wirelessly transmits calls & audio from smartphone to car FM stereo. Hands free calls function switches between incoming calls and music seamlessly. Smart APP supported with extra functions: parking positioning, voltage monitoring and frequency adjustment. The smart locator will automatically save the location of your car to the app when parking. It monitors the vehicle battery voltage in a real time, and gives warning of unusual condition. Also you can adjust the frequency via the app. Built-in protection system ensures the safety while charging your devices with the equipped dual 2 USB charging ports. Have one MEIDI SMART BLUETOOTH FM TRANSMITTER and make your road trip smart and fun.