Specification: Name: AK170 Power Amplifier Material: aluminum alloy Input voltage: DC 12V Rated power: 20W+20W MAX power:400W Rated frequency: 20Hz-20KHz Channel: 2CH Load impedance: 4-16Ω Signal to noise ratio: 90 decibels Distortion rate: 0.01% Size: about 133 x 113x 50mm Colour: Black Packing included: 1 * Power Amplifier 1 * User manual