In August 2002 the DB Regio electric locomotive fleet was expanded through the addition of another sub-class, namely Class 146.1, an improved version of the earlier Class 146.0, also built by Bombardier Transportation. Class 146.1 was conceived with a view to possible international duties, its capability of operating under 15 kV 16,7 Hz or 25 kV 50 Hz catenary has been achieved through several technical adaptations involving the main transformer wiring, the traction converter, and various other power components. Simultaneously, Bombardier engineers have succeeded in increasing the power output, from 4,2 MW for Class 146.0 to 5,6 MW for Class 146.1, without adding to the overall weight of the locomotive.