LP-2020A Class-D Hi-Fi Audio Mini Amplifier with US Power Supply Black Aluminum enclosure:Light weight,sturdy and stylish high-end appearance Built-in loudspeaker protection circuit triggers when the amplifier is turned on to protect speakers from high volume bursts of audio Power monitoring protection circuit: Output will be cut off when input voltage exceed 14.4 Volts DC or overheat etc Reduced signal interference and offer long operation life: State of the art design using surface mount components and advanced engineering for proven performance Cost effective: Low price and high performance,great for projects and DIY audio applications