Electric locomotives built for the electrification of the Gotthard mountain line after WW I, with similar frames and bodies, but different rod drives. The "Roebuck" Be 4/6 # 12320, built in 1921 by SLM and BBC for express trains has 4 driven axles with 1550 mm wheel diameter and 75 km/h max. velocity. The "grandmother" Ce 6/8 I # 14201, built in 1918 as Fc 2x3/4 # 12201 by SLM and BBC and delivered in 1919 for freight service, has 6 rod driven axles with 1350 mm wheel diameter and a maximum velocity of 65 km/h. The # 14201 is not operational any more since about 1982.
