Between the delivery of these locomotives and the completion of the Furka Base Tunnel, both members of the class were leased to the Rhaetian Railway, where they entered service hauling express trains on the Albula Railway. Since the opening of the Base Tunnel in 1982, they have been used exclusively on car shuttle trains between Oberwald and Realp.
The two locomotives represent a further development of the Ge 4/4 II class of the Rhaetian Railway. They are therefore classified as Ge 4/4 III under the Swiss locomotive and railcar classification system, even though the FO had not previously operated Ge 4/4 type locomotives. According to the Swiss classification system, Ge 4/4 III denotes a third series of narrow gauge electric adhesion locomotives with four axles, all of which are drive axles.
The Ge 4/4 IIIs develop 1,700 kilowatts (2,300 hp), have a top speed of 90 kilometres per hour (56 mph), and operate at 11 kV 16.7 Hz AC under catenary. They are the only mainline locomotives of the MGB not fitted with cogwheels for rack railway operations.
List of locomotives
List of Ge 4/4 III locomotives of the Matterhorn Gotthard Bahn