Pcb with LED display -support SD / USB Card Reader,FM radio,LED display -MP3 decoder,pcb assembly -DC 5.0V,IN -power on/off Pcb with LED display(Mini ... : Ordinary audio combination, Car audio, multimedia speaker, subwoofer, amplifier, electronic products and so on.-Key function: last songs, next songs, volume ... ) If you have any problems, please feel free to contact with us.pcb Pcb with LED display