Diesel locomotive were classified as DET 1 and DET 2 (). Due to shortage of petrol products during World War I, they remained unused for regular service in Germany. In 1922, they were sold to Swiss Compagnie du Chemin de fer Régional du Val-de-Travers (), where they were used in regular service up to the electrification of the line in 1944. Afterwards, the company kept them in service as boosters till 1965. Fiat claims a first Italian diesel–electric locomotive built in 1922, but little detail is available. A Fiat-TIBB diesel–locomotive "A", of 440CV, is reported to have entered service on the Ferrovie
TU10 diesel locomotive used, although most of them have been replaced by TU7 diesel locomotives or TU7A diesel locomotives. The production of narrow gauge locomotives was discontinued in the 2000s because of the demise in narrow gauge railways in Russia, such as forest railways, peat railways and industrial railways, and this led to a lack of suitable new or second-hand locomotives for the children's railways. The Kambarka Engineering Works began in 2008 with the development of a modern diesel locomotive especially for use at children's railways. Based on the experience with older models, the following innovations were implemented: The locomotives have two equal