This is a 4-channel amplifier for your reference: US-4028P 4-channel Power Amplifier Operating Voltage: DC 14.4V RMS Power at 4 ohms: 70w*4ch T.H.D.: <=0.02% RMS Power at 2 ohms: 140w*4ch T.H.D.: <=0.05% Maxpower at 4 ohms: 270w*4ch Bridged RMS Power at 4 ohms: 240w*2ch T.H.D.: <=0.2% Frequency Response: 20Hz-35KHz Input Level: 200mv-4.5v S/N Ratio: >=95db If you are interested in them, pls feel free to contact panyali at hotmail or unicarsaudio at yahoo. Thanks.