The WA-21N is a wall plate for stereo audio signals. It will convert an unbalanced stereo audio input to balanced stereo audio output over twisted pair which will be converted back to a stereo audio signal with a WA-22 twisted pair receiver.
Front Panel Connections - 3.5mm (F) input.
Rear Panel Connections - 6-pole terminal block output.
Audio Level Controls - Left & right.
Wall Plate Size - Single gang.