Locomotive 51 of the Limburgsche Tramweg Maatschappij was a Garratt locomotive. It was the only Garratt type locomotive in the Netherlands. The locomotive was designed for operation on the line Maastricht - Vaals, which required a locomotive with at least 5 coupled axles. A conventional locomotive of this size would experience too much rolling resistance in the many curves on this line, which were typical tramway curves of small radius.