Diesel locomotive 750 183 of the Slovak State Railways. In the early 1990s, there was a shortage of suitable locomotives due to the increase in passenger cars with electric train heating. Following positive results from retrofitting locomotives of the series 753, the CSD decided to retrofit all diesel locomotives used in passenger service with electric train heating. After the division of the state, "diving goggles" of this type were also in operation in Slovakia. To distinguish them from the original version, they were assigned the series designation 750 while retaining the order number.