This product is a car-specific Bluetooth car MP3 player, which uses a high-performance professional-grade Bluetooth module and MP3 decoder chip. It can play the music files in the TF card and send them to the car stereo wirelessly via FM. You can also wirelessly stream music from your phone to your car stereo via a Bluetooth connection. You can also use this device as a phone hands-free system. Communicate freely while driving. The device transmits wirelessly to your car stereo. No need to modify the car, listen to music while driving, hands-free phone calls, entertainment and safety. The device also has a car charging function, which can charge your digital products in the car. : 1. Power on and check the battery voltage 2. The car Bluetooth MP3 supports hands-free calls, built-in high-sensitivity microphone, HSP noise floor and echo suppression. 3. Support Bluetooth hands-free calls, built-in microphone, easy and safe to answer calls; caller ID 3. Noise processing CVC, wind noise suppression, and full-duplex call technology during calls; 4. Support mobile phone A2DP function, directly play high-quality mobile music after connecting to Bluetooth; support lossless audio decoding, high-resolution, high-performance stereo, support WMA, APE, FLAC, WAV and other lossless music formats. 5. Automatically reconnect when booting, and automatically enter the pairing state; 6. Support TF card expansion to play MP3/WMA format music; 7. It comes with a car charger with an output of 5V2100m, which can charge handheld terminal devices. 8. AVX port output and input. song name display 9. Automatic detection of car battery voltage, voice reminder, support instant voltage query 10. Bluetooth smart MP3 player, support mobile phone/network/all kinds of music APP software playback 11. Support mainstream map APP navigation voice broadcast and QQ/WeChat and other software language playback functions 12 Support TF card and U disk expansion playback 13. Upgrade the Actions 4.1 Bluetooth chip, the connection is more stable, and the automatic connection is faster. 14. Dual USB charging port QC3.0 5V/9V/12V, 5v2.4A, with intelligent identification, fast charging. 15. Support playback breakpoint memory function. 16. Support 3.5mm AUX audio interface to achieve high-quality audio output 17. Support button operation to switch folders to play 18. Knob design, one-button operation to adjust volume/answer/hang up/call back guide 1. start (1) Insert the device into the power socket of the car cigarette lighter, and it will automatically turn on after power on; (2) Select the transmitting frequency point on the device by adjusting; (3) Turn on the car stereo, set it to FM radio, and adjust the receiving frequency of the car radio to be consistent with the transmitting frequency of the device. 2. Adjust frequency and volume (1) This device supports full-frequency transmission, frequency range: 87.5MHz-108.0MHz. You can enter the frequency point adjustment mode by short pressing the frequency point selection key, use the up and down direction keys to adjust to the desired transmission frequency, and then press the frequency point selection key to confirm the frequency point. (2) Adjust transmission volume: In music playback mode or call mode, press and hold the up and down direction keys to adjust the volume. (3) Song selection: You can short press the arrow keys to select the song to be played; 3. Play the music in the TF card (1) Insert the TF card into the TF card expansion slot of the device, and the device will automatically recognize and play the MP3/WMA music files in the TF card. (2) Play/Pause: In the music playing state, a short key can switch between music playing and pausing. (3) Song selection: In the playback state, short press to select a song.