... SD card and USB disk, automatically read the first audio device you insert2, With AUX IN, it can compatible with MP3, MP4, CD ... SD card and USB disk, automatically read the first audio device you insert2, With AUX IN, it can compatible with MP3, MP4, CD ... range: 80HZ-20KHZImpedance: 4Power Voltage: USB / DC 5.0 VAccessory : Audio cable ,USB cable, lanyard , lithium battery ,manual. Warranty Card. alto ...