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.
1986 LEGO Sets
In 1986, LEGO's legacy of innovation and adaptability continued to flourish. This year was particularly notable for the introduction of the LEGO Technic theme, a departure from traditional brick-based sets. Technic offered a more complex building experience, introducing specialized pieces like gears, pins, and beams to enable the creation of intricate mechanical models with moving parts. This new line catered to older children and enthusiasts who sought more advanced building challenges. The Technic sets represented not just vehicles and machinery but the underlying principles of engineering and mechanics.