Features:          Audio mixer with 8 channels input and 2 channels output.               Each input channel can be adjusted volume individually.               With 2 master volume knobs for controlling the output volume.               Support MIC or LINE(4ch stereo & 8ch mono) input by adjusting switches.               Compact size and metal shell, lightweight and durable.               Dual power supply: power adapter(Included) and 9V battery(Not included).     Specifications:          Model: AM-228               Color: Black               Material: Metal               Power Adapter: US Plug               Input: 6.35mm Interface               Output: 6.35mm Interface               Item Size: 15 * 10 * 6cm / 5.9 * 3.9 * 2.4in               Item Weight: 705g / 1.6lb               Note:               The battery is not included.               You need to open the bottom cover with a screw to install battery.     Package List:          1 * Mixer               1 * Power Adapter(US)               1 * Cable