From 1977, ČSD had a total of 453 diesel-electric locomotives of a type manufactured that ČKD had presented in 1973. In addition, 41 more were built for private railways. The locomotives have a six-cylinder engine with 1,200 hp and with a maximum speed of 90 km/h, can be used for shunting and light freight trains. Ten more T 466.3s were built in 1988, which are designed for steep sections and have dynamic brakes. The two sub-series have been known as the classes 742 and 743 since 1988 and are still used today in the Czech Republic and Slovakia. Two came to Congo in 2011, for which they were converted to Cape gauge.