Programmable 4 Channel user station. Features a user programmable microprocessor assisted interface for the highest degree of flexibility and versatility. It is capable of two or four wire operation depending on configuration. Unique modular design supports five different package arrangements. Includes microphone limiter circuit, two powerful headphone amps, silent channel-select switching, VOX operation GPI output , IFB/ISO and simplified operational controls. User can talk independently or simultaneously on either two, three, or four channels. Part of RTS's unique modular packaging system in 1/2 rack by 1 RU metal housing for added durability.