I was at an exit in Burlington, NC and I saw 2 troopers walking out of the restaurant I was going in and they got in a black Dodge Charger completely unmarked. I went to my car to get my digital camera and the batteries were dead so I could not get the picture. As it drove by me I saw the radar units in the front and rear and lights in the grill. I never would have known it was a LEO. Living in NC that is the first time I had seen anything like that.