The DB228 Wall Direct Interface is an ideal impedance matching device for connecting any unbalanced stereo signal to a balanced system. Consumer audio equipment such as CD players, DVD players, MP3 players, phone, etc., may be easily connected to a professional audio system. In addition it will mix a microphone with a line level signal and send it out via a plugable barrier strip connector.Features: Level Control adjusts both inputs 3.5mm R and L mix to Mono Output is a screw terminal plugable strip Mounting for standard electrical wall box (not included) Trim is for standard Decor'a wall plate (not included)* Will pass phantom power Decora plastic cover in image is not included. Transformer isolation device Passive - no power required Stereo 1/8" (3.5mm) Input Balanced plugable barrier strip Output Connector The DB228 is an ideal impedance matching device for connecting any unbalanced stereo signal to a balanced system. Consumer audio equipment such as CD players, DVD players, MP3 players, phone, etc., may be easily connected to a professional audio system. In addition it will mix a microphone with a line level signal and send it out via a plugable barrier strip connector.*Decora plastic cover in image is not included.