Main control IC: AC 6921; Bluetooth IC: AC 6921 Bluetooth version is 5.0Music : MP3/WMA/WAV/FLAC/ lossless Bluetooth calling function; recording function; Folder switching functionRadio FM frequency: 87.5-107.5 MHZSupport function introduction: support MP3 / USB / TF / LINE IN / FM / BLUETOOTH / remote control connection / DC 12VButton and interface function1. PREV: Twist to the left to select the previous song; : Twist right to select the song;2. IR: infrared receiving module;3, MIC: support call and recording functions;4. USB interface: connect U disk (maximum support 32GB);5. LCD screen: synchronous display of ;6. SD card slot: connect SD memory card (maximum support 32GB);7. AUX interface: audio input interface;8. Volume knob: control the volume;9. REC: Press and hold the REC button to start recording, press the REC button again to cancel the recording function and play the recorded file; when recording, you need to connect a storage device, such as a U disk or TF card;10. REPEAT: Press the single loop function , press it again to cancel the single loop, and in sequence;11. -: The short key is to switch to the previous folder, and the long press is to rewind;12. +: Short key is to switch to the folder, long press is fast forward;13. PLAY/PAUSE: Short press is to switch between pause and play; long press is to radio FM automatic station;14. MODE: Switch between USB / TF / FM / AUX / BLUETOOTH;Material: plasticcolour: blackPackage Contents:1 x decoder board1 x remote control4 x linesOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.