item specifics: <br /><br />     and high quality<br />    work: d class<br />    quiescent current: 20ma<br />    operating voltage:dc7.5-15v<br />    rated output power: 10w+10w (8?)<br />    frequency response:20hz to 50khz<br />    recommended supply voltage:12v，the center pin of 12vdc is +.<br /><br /><br />package included: <br /><br />    1x audio stereo amplifier board