The NS 6400 was built through a cooperation between MaK and Brown, Boveri & Cie in Mannheim, with 120 units having been built between 1988 and 1992. It was again based on the DE 1002, which had been built in twenty-four copies for the Häfen und Güterverkehr Köln 1982 and 1993. Another variant of the DE 1002 and NS 6400 is the Eurotunnel Class 0001, built in 1991. The Di 8 was technically similar, although slightly larger and more powerful, than the Dutch and German variants.