Starting in 1898, the Swiss North Eastern Railway got 25 4-4-0 express locomotives from the SLM. They were called A 2/4 and were two-cylinder compounds. Being the only inside-cylinder locomotives of the NOB, their designers hoped to get smoother running characteristics. The Walschaerts valve gear was located on the outside.
On flat lines, they were usually used in trains of 300 to 600 tonnes and 200 to 240 tonnes on 1.2 percent. After the NOB became part of the SBB in 1902, the SBB ordered 25 more. The newer locomotives had a steam and a sand dome, while the earlier ones didn't have any domes. Only the three oldest were retired in 1917, all others followed in 1925.