JaJaBor FM Transmitter FM Modulator Type C 3.1A USB Fast Charging Car Charger Handsfree Bluetooth 5.0 Car Kit Mp3 Player 1.Bluetooth V5.0 2. Support ambient light 3. Battery voltage detection 4. Auto power off memory function 5. Support FM stereo transmission technology 6. Support U disk playback 7. Does not support TF card music play 8. Support WMA, MP3, WAV, FLAC music format files 9. Wireless support A2DP, AVRCP, HFP, HSP 10.Bluetooth support hands-free calls 11. Support Bluetooth compatible stereo music DSP technology 12. Dual USB 3.1A+1A, PD 18W quick charge 13.one key EQ Package includes: 1 * Car Handsfree FM Transmitter 1* user manual Question and Answer Question 1 What is the FM transmitter? Answer FM transmitter is a very small FM Radio Transmit Station with a broadcast range of <5 meters. Main function: Transmit the audio to your car FM radio via the same FM bands, Then you can hear this audio in the car speaker. Question 2 Why my car FM Transmitter function is so noisy? Answer FM Transmitter transmits the FM band in 5 meters. We know the FM radio station is a very wide range, if we set the same band with radio, our signal will affect a lot. So we can follow the steps as below, 1. We adjust our car FM to the band without the radio station, like 108.0MHz. 2. We change our device FM band to the same band with car FM -108.0MHz. 3. We can play music via TF card or Bluetooth, check the quality of sound. Question 3 When playing music, get an incoming call, why the sound volume becomes louder or lower after answering it? Answer Because the calling volume is controlled by the "Calls "and music volume is controlled by "Media "in your phone volume settings. So you can modify the settings on your phone to let the sound more comfortable.