The OM range by Deutz consisted of small diesel shunters for industrial railways built in the thirties and early forties. They were powered by two-stroke engines with one to four cylinders. Their development focused on simple construction and cheap maintenance. Most had two axles, where one was powered by a chain and the other was connected to the first one by coupling rods. 

The most numerous model was the OMZ 122 R with 176 produced, where the Z stood for two (zwei) cylinders. While the 1 denoted the first generation of the engine and 22 denoted the cylinder stroke in centimeters, R stood for standard gauge (Regelspur). There were also narrow gauge variants like the OMZ 122 F that was developed for field railways and had a gauge of 600 mm. It only had half the weight of the standard gauge variant and a somewhat lower power.

The SM02 was the first diesel locomotive built in Poland. From 1952, 581 of these small shunting locomotives were manufactured in the Feliks Dzierzynski locomotive factory (later Fablok) in Chrzanów and sold by the manufacturer as the Ls40 type. The Polish State Railways only procured twelve examples, which were classified there as the SM02 series. With a maximum speed of 11 km/h, a range of 60 km and an output of 44 hp, they could not be used in larger train stations, which is why they were mainly used in industrial companies. The power was transmitted mechanically to one of the axles, which drove the second axle by means of coupling rods. Over time, many of the locomotives got a new type S324HL engine, which delivered either 60 or 75 hp. Many engines were still in use up until the 1990s, but most of them became superfluous due to the abandonment or dismantling of many industrial tracks. A few are still in use today, others are preserved either as a memorial or in the museum.