The 71-608 (in colloquial language KTM-8) is the Russian motor four-axle high-floor tramcar. These rail vehicles are produced by Ust'-Katav Vagon-building plant (UKVZ, УКВЗ, Усть-Катавский Вагоностроительный Завод имени С. М. Кирова - Russian abbreviature and full name). "KTM" means Kirov Motor Tramcar (Russian: Кировский Трамвай Моторный). This abbreviature was producer's official trademark before 1976, when new designation system for tram and subway rolling stock was introduced in the Soviet Union. After official abandoning KTM trademark it still lives in everyday conversations of Russian tram workers and enthusiasts.
- 71-608 - two prototypes from 1988, used in Tver and Moscow. Withdrawn.
- 71-608K - standard model 1991-1993
- 71-608KM - standard model 1993 - 2000s