The RS-603 is a 2-channel 3-pin dual-listen monaural beltpack with a 4-pin male headset connector and 3-pin female/male loop through intercom line connectors. It also has a 2.5mm AUX headset connector and an RS-232 data connector for programming.  Two channels of audio are passed down a single 3-pin XLR with TWC-701 or TWC-704.

The beltpack can be programmed using the V-pack software, which does not require beltpack to be opened or any dip switches changed, etc.

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