 From 1896 they were reclassified as K IV and from 1900 as IV K. The 'K' stood for "Kleinspur" or 'small gauge'.The IV K was used both in front of passenger trains and also goods trains and proved itself so well that it ousted the other locomotive classes completely on several lines.Five locomotives (123, 139, 147, 148 and 174) were deleted from the roster after World War I.