The CH-RCA7 is a video cable for reversing cameras and carries the video signal from the camera to the monitor or display.
The cable is 5m long and has a thin wire included which is used with the reverse trigger required on many monitors to turn on the LCD when in reverse gear and this wire will be connected to the reverse lamps in the tail light assembly. Connecting to the reverse lamps is generally only done with older vehicles and is not possible on many modern cars and can cause problems with the electrical system in the worst case and this should only be carried out by experienced professional installers.