Swiss Locomotive and Machine Works
Swiss Locomotive and Machine Works (German Schweizerische Lokomotiv- und Maschinenfabrik; French Société Suisse pour la Construction de Locomotives et de Machines; or for both, SLM) was a railway equipment manufacturer based in Winterthur in Switzerland. Much of the world's mountain railway equipment was constructed by the company.
Source: Wikipedia — Swiss Locomotive and Machine Works (CC BY-SA 4.0)