Can play MP3 format music from U disk and SD/MMC card directly,support FM stereo radio, high-power four-channel professional power amplifier integrated circuits,minimal distortion but strong power,Amateur professional level input and operational amplifier IC for circuit design,transparent and bright sound Filtering and anti-large-capacity power circuit,Four sound field patterns,Two main channels and two surround channel output,Input voltage:DC 12V,Frequency response:20Hz - 20KHz Harmonic distortion:0.05pct and less ( 4W 1KHz ),SNR:85dB,High control:12dB, control:12dB Signal level:220MV 47K,FM frequency response:87.5 - 108MHz,Power:20W x 2 color:red Material:aluminum alloy Product size:15.5 x 8.5x 4cm Package Contents: 10 x - 400 Power Amplifier 10 x Remote Control 10 x English User Manual Only the above package content, other products are not included. Note: Light reflection 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.