 Because the three railcars weren't enough to completely replace the slower steam trains a fourth railcar of the same series as the first three was bought in 1953.It received a bigger cargo hold and was classified as BDhe 2/4 and got the number 4.To add to the passenger carrying capabilities of the line even more a class BDhe 4/4 from the same makers arrived in 1964 and, again from SLM / BBC, in 1986 two railcars (BDhe 4/4), numbered 21 and 22, arrived with single end driving trailers (Bt) numbered 31 and 32 which were nearly identical as the railcar 15.