They were the first six-coupled engines in Bavaria and were developed specially for the route between Neuenmarkt, Wirsberg and Marktschorgast. This route had inclines up to 1:40. The loco had an inside frame, a boiler barrel without a steam dome, an inside Stephenson valve gear, single-sided, suspended Taschenkulissen and a rectangular ballast tank on the boiler barrel to increase the adhesion effect. A total of five were built by Maffei. They were named: SCHARRER, BEHAIM, LEIBNIZ, SAALE and SCHNEEBERG. There is a finely detailed 1:10 scale model of BEHAIM in the Nuremberg Transport Museum.
They were equipped with Bavarian tenders of the class 2 T 4.2 type.