7 Colorful LED Strips: The FM transmitter bluetooth car adapter supports 7-color LED backlight, 7-color LED breathing light makes driving more fun, shines to amplify the atmosphere and also makes it easier to enjoy driving. use and night driving. Equipped with an LED voltmeter that shows you your car's battery status to keep you updated on the status of the vehicle. Dual Smart USB Ports & Safe Charging - Equipped with 2 USB ports (5V-2.4A and 5V-1A), you can charge two devices simultaneously. Built-in overcurrent protection, overvoltage protection, intelligent temperature control, short circuit protection, it will effectively ensure safe charging. Car battery voltage detectionThe transmitter FM will display car voltage when plugged into cigarette lighter. Keep abreast of car battery health at all times to avoid trouble while driving. Easy to UsePlug the Bluetooth FM transmitter into the cigarette lighter from the car, select an empty FM frequency (range 87.5-108MHz) on your car radio, connect your phone's Bluetooth to the hands-free car kits, then tune it to the same frequency. After successfully paired, it will transmit music from your phone to the car stereo system. Best Hands-free Calling & Voice Navigation: One click MFB button to answer/redial/hang up or reject calls; Seamlessly switches between incoming calls and music. Besides, this FM transmitter supports the existing navigation app on your phone, you don't need to look down at the phone to ensure safe driving.