Meccano introduced its OO scale trains in 1938 under the name 'Hornby Dublo'. The locomotives were diecast metal, and the carriages and wagons were generally made of tinplate. This was a very well planned range of electric and clockwork models, successfully consolidating 12 V DC as the standard for OO scale. This led to the adoption of OO as a broadly accepted modelling standard in the UK, whereas much of the rest of the world adopted HO scale. As for their O gauge locomotives, electric Hornby Dublo locomotives ran on a third rail electric system with the track built on a pressed tinplate base.
In 1964, Lines Bros Ltd., the parent company of rival Tri-ang Railways, purchased Meccano Ltd., and merged Hornby and Tri-ang into 'Tri-ang Hornby'. The former Hornby line was discontinued in favour of Tri-ang's less costly plastic designs. The Hornby Dublo tooling was sold to G & R Wrenn, which continued to make most of the loco range and 'superdetail' rolling stock. Remaining stocks of 0 gauge were either scrapped or sold to the local retailer Hattons