Specifications: Product name: USB Bluetooth FM transmitter Product model: SFD-FM02 Bluetooth version: V5.3 Working voltage: 5V Effective distance: Within 10 meters Audio output: FM transmitter FM frequency range: 87.5MHZ-108MHZ Default frequency: 95.0MHZ Signal-to-noise ratio: ≥95db Answer the phone: Support Automatic return connection: Support Power supply mode: USB power supply (5V) Features: USB interface The USB interface is used for the power supply. When using it, you can plug this product into the USB interface with an output voltage of 5V, for example, the car comes with a USB interface (5V), and the car charger interface (5V). Multi-function M button: 1. To adjust the FM frequency, long press the M button, and the screen starts to flash to enter the FM adjustment mode. Long press or short press the "+" and "-" buttons to adjust quickly and slowly. After adjusting, click the M button to confirm, and the screen stops flashing. 2. When playing a song, click the M button to pause and play. 3. Answer the call: When someone calls in, you can click the M button to answer the call. Multifunctional "+" and "-" buttons 1, "+" button: click the next song, and long press to increase the volume, in the FM adjustment mode, click and long press to adjust the FM channel. 2, "-" button: click on the previous song, and long press to reduce the volume, in the FM adjustment mode, click and long press to adjust the FM channel. Instructions: 1. Plug FM02 into the USB interface in the car with an output voltage of 5V. 2. Set the FM frequency band through the multi-function M button, then turn on the car radio, and adjust the FM frequency band of the radio to be consistent with that of FM02. 3. FM02 has an FM frequency automatic memory function, every time it is powered on, it will default to the FM frequency of the last use. 4. After the FM frequency band is set, find the Bluetooth pairing name: FM02 in the Bluetooth settings of the mobile phone, and click to pair. Then the music played by the mobile phone will be played on the car's speakers. 5. Adjust the volume: When you are playing music, you can adjust the music volume of the mobile phone to the maximum, and adjust the car volume to a moderate level. It is not recommended to turn up the car volume too much, because the louder the car volume, the more serious the noise and distortion will be. Notes. 1. The default frequency band of FM02 is 95.0MHZ, which can be used directly. If the playback is noisy, you can adjust to other frequency bands. 2. When you turn on the radio of some models, the power of the car's built-in USB port will be turned off. In this case, the FM02 cannot be used if it is plugged into the built-in USB port. In this case, the FM02 can be used by plugging it into the cigarette lighter and car charger. The FM02 can be used with a power supply on the interface (USB output voltage must be 5V). 3. The FM02 is used in some original automobile USB ports, which may be too noisy or unusable. It is recommended that the FM02 be plugged into a cigarette lighter car charger. 4. The FM02 does not have an automatic shutdown function, so it is recommended that it be unplugged from the USB port when not in use. 5. When the FM02 cannot be searched in the Bluetooth settings of your cell phone or cannot be paired after searching and clicking, it is recommended to clear the previously connected Bluetooth devices in your cell phone and restart your cell phone to try again. Package includes: 1*Bluetooth transmitter