At the Danish State Railways, the class F comprised three different types of tank locomotives with a 0-6-0T wheel arrangement. The four examples of type I were originally tender locomotives built in 1873 by the British company Hawthorn, Leslie & Company for the Jysk-Fyrenske Jernbaner. In 1889 and 1890 they were converted into tank locomotives. Only eight examples belonged to type III, which were built by SLM in Winterthur in 1917 and delivered to Denmark after the end of the war. They were the only superheated steam engines in the series.

Type II accounted for by far the largest share with 120 units. It was unusual that these locomotives were built by different manufacturers in different countries over a very long period of time. From 1898, ten pieces were made by an Italian company Costruzioni Meccaniche di Saronno, which belonged to Maschinenfabrik Esslingen. Another 20 units from Breda (Italy), Hanomag and Henschel (Germany) and Smith, Mygind & Hüttemeier (Denmark) followed until 1903. Two further batches of 30 and 45 pieces each followed between 1909 and 1923 by Borsig and Hanomag (Germany), Frichs (Denmark) and Les Ateliers Métallurgiques Tubize (Belgium). Another 15 engines from Frichs followed in 1949.

The fact that 51 years after the first deliveries new locomotives were built in a technically almost unchanged design shows that even small tank locomotives with saturated steam were sufficient for shunting and that no more complex machines were required. Even the Allan valve gear was retained, which at that point had actually been out of date for a long time. The only changes were more modern buffers and a larger coal bunker. In the meantime, the existing locomotives had been fitted with air brakes instead of steam brakes. Nevertheless, they were phased out in the 1960s, since diesel locomotives were now available for shunting.

After the passenger trains on the main routes on Jutland and Funen had reached a weight of 800 tonnes, the pulling power of the Litra P (II) Atlantic locomotives reached their limits. In view of the good experiences with the Prussian P 8, a new locomotive with the wheel arrangement 4-6-0 was developed with the R (I) and ordered from Borsig.

At 1,866 mm, the coupled wheels had a slightly smaller diameter than those of the P (II). The saturated four-cylinder compound engine now received a successor in a simple superheated two-cylinder engine. By relocating the cylinders to the middle of the bogie and driving the first axle, smooth running could be maintained at a high level. The boiler had roughly the same dimensions and was able to produce the same output despite the boiler pressure being reduced from 15 to 12 bars. The narrow and deep firebox was designed for high quality British coal and compensated the smaller grate area with a larger area of the walls.

R 935, probably on a Borsig works photo

After the first twelve vehicles, a further eight were to be procured by Borsig, but this was not possible due to the First World War. Instead, the Swiss locomotive factory in Winterthur delivered the remaining machines. These had a steel firebox, which was replaced with a copper one after the war. The locomotives were eventually retired between 1958 and 1972. An example damaged in an accident was restored and then came to Danmarks Jernbanemuseum in Odense. Unfortunately, it was scrapped in 2018 along with about half of the museum's exhibits.