
In 1972 LEGO released the 4.5V and 12V train sets as part of the Blue Era which was named because of the rail color. These train sets used additional conductor rails mounted between the standard 4.5V rails and 12V motors contained in the same housings as the 4.5V motors, but with additional metal contacts attached to the bottom of the housings.
1985 LEGO Sets
1985 expanded everyday play in Town—airports, transit, and rescue—alongside incremental growth in Castle and Space. Technic emphasized functional builds with working steering, suspensions, and gear trains, continuing to position the theme as LEGO’s bridge to real-world mechanics.