Crystal Clear Music Streaming - T25 is designed according to static anti-mechanical principle and equipped with CVC noise and wind suppression technology which realizes full-duplex sound quality. You can stream music to your car stereo via Bluetooth / USB Flash Disk (32 GB) / Micro SD Card (32 GB). WMA/ MP3/ WAV/ APE/ FLAC music formats are all supported. Dual USB Smart Port and Safe Charging - Comes with 2 USB ports (5V at 2.4A and 5V at 1A) , you can simultaneously charge two devices. With the built-in functions such as overcurrent protection, overvoltage protection, intelligent temperature control, short circuit protection, it will effectively ensure safe charging. Hands-free calling and Voice Navigation Bluetooth provides a stable connection, while Noise Cancellation (CVC) technology grants an amazing hands-free calling experience. Besides, you can also get clear voice navigation from your phone's app. Car Battery Voltage Detection and Blue Ambient Light - When the FM transmitter is plugged into the cigarette lighter, the voltage of the car will be displayed. Keep abreast of car battery status at all times to avoid trouble while driving. With the blue backlight circle around this car charger, your operation for safer driving will be greatly simplified. Wider Range and Compatibility - This Bluetooth transmitter is well compatible with most smartphones and more devices with Bluetooth function. Once turned on, it will automatically connect to the stored paired Bluetooth device. Besides, with the wider frequency range from 87.5MHz to 108MHz, you can get a more stable and consistent music experience without interference. Plug this FM transmitter into the cigarette lighter socket. Pair your phone to this device via Bluetooth as T25. Tune your car's FM radio to a blank station (87, 5 to 108.0 MHz) and tune this FM transmitter to the same. Hands-free callingJust click a button to answer, redial, decline or end a call. High-performance microphone with Noise Cancellation (CVC) technology gives you a crystal clear call. Perfectly switch between incoming calls and music. Navigation Broadcast With this Bluetooth FM transmitter, you can get clear voice navigation from your phone's app. The navigation volume will be automatically adjusted when playing music. No more hassle, however, full of exploring during your trip. Car Battery Voltage Detection It is equipped with a voltmeter to show you your car battery status. The voltage should be between 13.2V and 14.7V when your car is running and moving. The voltage should be 12.2V to 12.8V when your car is parked and the ignition is off.