The TEP70 is a main line single-unit diesel locomotive, rated at 2,964 kW (3,975 hp), with AC/DC transmission and individual axle traction control, designed to haul passenger trains on the Russian gauge railway network of eastern Europe. As of 2022, it is still in service in Russia, Ukraine, Belarus, Estonia, Latvia, Lithuania, and Kazakhstan. It is the successor to the TEP60, with many design elements is derived from that locomotive; however, the engine was replaced by a four-stroke one. TEP70, especially its experimental batch (first 7 locomotives), incorporated some features of British Rail HS4000,[1] for example, its bogies and some elements of driving control equipment. Later batches of this locomotive incorporated some design features from TEP75 experimental locomotive and predecessor TEP70. Final batches, produced until 2006, also had several important improvements.