In World War I, the Pillkallen Light Railway, situated in the region around Königsberg (today Kaliningrad in Russia) was re-gauged from 750 to 1,000 mm (metre gauge). This railway was part of the larger ODEG (Ostdeutsche Eisenbahn-Gesellschaft, East-German Railway Company). The only locomotives for their network around Pillkallen that spanned around 60 km were four 2-6-0T tank locomotives supplied by Jung. They got the numbers 21 to 25 and had a combination of side tanks and a well tank between the frames.
When the railway fell into Soviet hands in World War II, operation was stopped and somehow four of these locomotives had been rescued into the West. No. 21 was in Western Germany and was used by the Lokalbahn Speyer-Neustadt. It received the number 99 241 and was withdrawn in 1957. 23, 24 and 25 were located in Eastern Germany. 23 was used on the Spreewaldbahn as 99 5633 until 1970 and is today running on the preserved railway Bruchhausen-Vilsen–Asendorf. The other two were given to the Soviet Union in 1946.