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
TU7 diesel locomotive the TU7 - TU7A () diesel locomotive, is a series of diesel locomotives currently used on the Vietnamese railway network. With 77 locomotives D4H in service throughout the country as of 2005, it is the most common type of locomotive in use in Vietnam. The series was originally procured from the Soviet Union after the Vietnam War. TU7 diesel locomotive TU7 (ТУ7) - Soviet, later Russian diesel locomotive for gauge – . The TU7 () was developed in 1971-1972 at the Kambarka Engineering Works to replace the aging locomotive classes TU4 () and TU2 (ТУ2). There were 3,361 locomotives constructed,