... , common use production efficiency:1000 pcs per day Product Name SD Card/USB mp3 playerMode No. ES-213Function Mp3 player + FM ... *3.5 CM More information Music brodcast mode: Supporting SD /MMC card or USB drive to play music Shell color choice: ... Key function: previous, next, pause, volume regulating, FM searchingWith earphone socket, can be connected to earphone or multimedia speaker directly