In Italy and Germany; however, not on a Subaru. Single red lamp with a widely defused light mounted under the rear bumper (centered and pointed downwards aimed at about 10 feet in back of the car). These are required in Italy, and I believe were optional in Germany at the time. Powered by the same switch that activated the fog lights on my Fiat 128, Opel Rekord, Peugeot 403, and a couple of other cars that I drove there.
