The Ge 4/4III is a type of four-axle electric locomotives with AC traction motors developed for the RhB starting in 1989. They were needed for the 19 km long Vereina Tunnel then under construction and have a top speed of 100 km/h, but are also suited for lines with tight curves like the Albula Line. A large part of the electronics was taken over from the SBB Re 460.
In 1993 and 1994, SLM and ABB built the first nine locomotives. Another batch of three was built in 1999, with ABB now being part of Adtranz. The twelve locomotives received the numbers 641 to 652 and were named after villages and small towns in Grisons. They were modernized from 2016 to extend their lives beyond 2035. In addition to the RhB, the MOB and BAM have ordered similar locomotives.