In 1890, the Visp Zermatt Railway received its first four 0-4-2T rack locomotives from the SLM. They were among the first ones of the Abt system. All four cylinders worked with high-pressure steam and to provide space for the inner ones which powered the rack wheels, the frames were placed on the outside of the adhesion wheels. Top speed in adhesion mode was 25 km/h and limited to 10 km/h on rack sections. After the first four locomotives, four more followed until 1908 of which the last two were somewhat heavier.
Between 1913 and 1926, six were superheated, what increased their weight by a tonne. When the line was electrified in 1929, the locomotives were withdrawn from regular service, but five were kept as a reserve. Number 6 was sold to a new operator in the industry, while 7 was used for construction trains and some excursions. Both are now owned by the Furka Steam Railway, but only 6 is operational, while 7 was moved into storage in 2011.