The class 301 was a four-cylinder Pacific of which two each were built by MÁVAG in 1911 with simple and compound expansion. The simple locomotives were numbered 301.001 and 002, while the compound locomotives were 301.501 and 502. They looked fairly impressive with conical smokebox door and wind cutter cab. The drivers measured only 1,826 mm for better pulling power on mountainous lines. The boilers were superheated and had a large grate of 4.846 square meters. The compound variant was designed after the De Glehn system and operated at a pressure of 16 bars, while the simple variant was set at 12 bars.

Approved for 100 km/h, they managed to haul a 700-tonne train with 120 km/h on the level on test runs. Comparisons showed that the compound variant was more powerful and economical than the simple variant, but more complicated to maintain and operate. In the result, the next 18 locomotives were built in the simple variant. Production stopped in 1914 due to World War I. They were withdrawn between 1966 and 1968.