The Übergangskriegslokomotiven (literally: provisional war locomotives) were austere versions of standard locomotives (Einheitslokomotiven) built by Germany during the Second World War in order to accelerate their production.
In the Second World War the requirement for motive power, especially goods train locomotives, rose sharply.
Characteristic of ÜK locomotives are e.g. disc wheels on the carrying axles and the omission of the front side windows in the driver's cabs.
Even preheaters, feed pumps, Frontschürzen, smoke deflectors and other equipment not essential for the operation of the locomotives were sometimes left out.
As a result, genuine war locomotives (the Kriegslokomotiven) were developed by the Deutsche Reichsbahn.