4512V covers the LEGO trains of the 4.5 V and 12 V systems from the 1970s and 1980s. The 4.5 V trains ran on batteries carried in a wagon or tender, while the 12 V trains drew power from conductor rails laid between the running rails, fed by a transformer with a speed control. Until 1980 the track was blue, which gave these years the name of the Blue Era.
1981 LEGO Sets
1981 strengthened the bridge from DUPLO to System through Fabuland, featuring animal characters and story-led builds. Town expanded urban life with new services and vehicles, Space continued its exploration motif with larger craft and surface equipment, and 12V Trains saw ongoing refinements for more sophisticated layouts.