Key Description:USB: Connect U disk (maximum support 32GB)LED: digital screen display, red infrared receiver moduleTF: Connect TF memory card (maximum support 32GB)AUX: Audio input interfaceVOL-: Short press is to select the previous song; long press is to decrease the volumePLAY/PAUSE: Short press is to switch between pause and play; long press is to automatically search for radio FMVOL+: Short press is to select the next song; long press is to increase the volumeSpecial function description:1. Support folder playback2. Support call3. Support recording. Recording only supports operation in TF mode or USB mode.4. Support power off memory (support the last mode and volume memory. (The last setting before power off will be played after power on))5. Color screen display6. The power supply voltage supports between DC4.2v-12v, and the current is between 0.5-2A.7. Can be directly connected to speakers, with power amplifier and decoding functions.8. Support song format MP3 /WMA / WAV / APE / FLAC9. Main function MP3/USB/TF/LINE IN/FM/BLUETOOTHemote control/DC12V10. The Bluetooth version is 5.011. Chip model Zhongke Lanxun 5536B12. Power 6W, true stereo dual channel. (2*3W)