Approach Tech DVR-3704T - Manual (Page 7)

Easy field firmware update via USB device can be performed by the end user.
Built-in USB connector to save image(s) for an individual channel to an USB device.
4 BNC video input channels.
4 alarm inputs and 1 alarm output.
Audio recording.
Quick setup menu.
Disk-full warning.
Supports factory default menu setting.
Supports Play/Reverse-Play/Pause/Stop/FF/REW for playback.
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