This locomotive is a switcher that has been also used for short run trains, when high power output is not required for a long time, or in light rail branches. They belong to a series of switchers listed as: U5B, U6B, U8B, U10B an UM10B and were built in the United States, during the 60's and 70's, by General Electric, using a Caterpillar diesel engine. After the mainline dieselization process, in the second half of the 50's, the remaining steam locomotives were used as yard switchers until early 60's, when the diesel switchers arrived.

3039 - MRS
  

3037 - RFFSA