The E class was the most numerous single class of locomotive in the world, with around 11,000 manufactured in Russia and other countries such as Czechoslovakia, Germany, Sweden, Hungary and Poland. This class even far outnumbered the German DRB Class 52 2-10-0 Kriegslok. The class was eventually superseded by the SO class which can be considered a further development of the E class, the L class and the FD class . Despite being superseded, it was not replaced, and the class was widely used until the end of steam in Russia.