Grunberg was a French microcar manufacturer associated with Rodolphe Grunberg, who built a small two-seater roadster known as the RG 125 in 1960. The RG 125 was powered by a 125cc single-cylinder two-stroke engine. Weighing around 150 kilograms, the car was capable of reaching a top speed of just over 40 mph (64 km/h).