The London Underground 1986 Tube Stock consisted of prototype electric multiple units that led to the development of the 1992 Stock. Two prototypes were built by Metro-Cammell, and the third by BREL (subsequently ABB, Adtranz, now Bombardier Transportation). The (then) London Transport were looking to the future, so they contracted for three different prototype trains to be built. The public consultation results show that the BREL-built blue prototype was the favourite, and therefore the train provided the core design basis for the 1992 Stock.