Product Specifications: 1. Built-in Bluetooth + microphone. 2. Hands-free calls 3. Supports Advanced Audio Distribution Profile 4. Off time display function 5. Digital high-quality FM stereo radio、 6. Preset 18 stations (Radio frequency: 87.5-108 MHz) 7. Support USB / SD / MMC card reader (Maximum support 32GB)8. Support Audio: APE / FLAC / MP3 / WMA / WAV、 etc. 9. Support folder function 10. Support breakpoints and ID3 Play 11. Support Remote control12. Rotary Volume Control 13. MP3 randomized、 10 track up / down playback 14. Electronic control volume treble、 bass、 balance and fader 15. Multiple EQ Scene Selection: jazz、 rock、 pop、 classical、 etc. 16. Mute and Loudess control 17. L / R RCA audio output jacks (Subwoofer can be accessed)18. 4-channel high power output (4 loud speaker、 I tested the sound quality is super good.) 19. Operating voltage:9-14V20. Machine size: 178 mm (W) * 50MM (H) * 125 mm (D) 21. Overall dimensions: 188 mm(W)* 58mm (H)