I have two cameras mounted high on the back of our motorhome. One is aimed long for the traffic view, and the other is aimed down for the view from the rear bumper back about 20 feet. The dash monitor can be set to turn on the selected camera only when backing up or left on all the time. I prefer having it on all the time while underway with the long view selected, switching to the short view when backing in to a tight spot. I can easily stop within an inch or two of rear obstructions, sometimes freaking out onlookers. :)