Usually it is the left rear light only (so not to be confused with brakes) and is really needed in Europe where even in dense fog it is not unusual to see cars going 80+ mph. I remember driving to southern Germany from Frankfurt in our Volvo through dense fog. I was going 45 mph and I was passed numerous times by Mercedes, etc and then I came around a corner on the autobahn and there were about 15 cars in various stages of carnage...felt like I was driving through the aftermath of a battle... the rear fog light is important in Europe, but probably just confuses Americans who are unaware of it. Bob in C Springs
2001 Boxster S with REAR fog light.
