QTX: 170.205UK, Mini Line Level Mixer, 4 Stereo Jack Inputs, 2 Outputs, Compact Design, Battery or Adaptor PoweredMini Line Level Mixers Compact mixers with high impedance jack inputs suitable for auxiliary line level or instruments, mixing to a master jack output. Available as either 4 mono or 4 stereo version with separate volume controls for each input and master output. Powered by 1 x 9V battery or optional 12Vdc adaptor. Available in mono or stereo versions Requires 9V (PP3) battery or 12Vdc power adaptor