Item Type: Sound Mixer Passive Material: Acrylic Input Impedance: 10K to 47K Output Impedance: 2.5K to 10K Gain: -12dB Maximum Interface: 3.5mm Sound Interface Package List 1 x Sound Mixer 1 x Instruction Manual 1 x Foot Pads (4pcs) 1Applications: Sound mixer for extended control of tuning, mixing instruments, CD players, tape players, computers, cell phones, tablets. 2Plug And Play: Stereo mixer is small and portable, plug and play, no external power required. It is very convenient. 3Control Knobs: Stereo mixer is a four way independent control knob, for each channel volume fine amplification, without interfering with each other. 4Stereo Interface: Sound mixer is four in one out, all 3.5mm stereo input and output, can also be used as a 4 in 1 out stereo splitter, clockwise rotation to adjust the volume. 5Premium Material: Stereo mixer is acrylic material, gold plated interface can effectively avoid poor contact to ensure stable signal transmission.