Since the railroad saw itself subject to increasing competitive pressure from freight service by truck as early as the end of the 1920s, the German State Railroad Company recognized the necessity to accelerate freight service by rail.
The "Leichten Eilgüterzüge" (Leig or "Light Weight Express Freight Trains") were created for less-than-carload-lot freight. These trains were usually composed of 1 to 2 "Leig" units. The "Leig" unit usually consisted of 2 two-axle boxcars that were permanently coupled to one another and connected by a diaphragm. This allowed the express freight to be sorted en route. The German Federal Railroad maintained the light weight express freight trains. The old "Leig" units were only capable of a maximum speed of 65 km/h or 41 mph. The DB therefore purchased new double cars that could run as fast as 100 km/h or 63 mph. "Leipzig" design cars still being purchased at the end of the 1940s served as the basis for the new type Gllm(g)hs cars. A total of 240 cars were paired up to form "Leig" units. These cars were in use on German routes until the end of 1978.