Inspired by the Prussian State Railways class P8 from 1906, a sixcoupled general purpose locomotive disignated class B was delivered in 1909. The class proved excellent for a kinds of duties and was used for hauling freight as well as heavy passenger trians. From 1909 to 1919 it was built in 96 examples. The class B was also used by a number of private railways, among them the BJ, SDJ, SWB and SNJ. As late as 1944 SWB (Stockholm-Vasteras-Bergslagens Jarnvagar) took delivery of 3 class B engines, which were later taken over by the SJ. The total number built was thus 99 examples.