According to the Plarail history on Tomy's site, they didn't produce a locomotive modeled after a real engine until 1971. Even then, it was based on the D51. They certainly could've used a Tomy mechanism since they released their first motorized engine in 1961 but I would inclined to suspect they used a toy or model readily available from U.K. retailers in the 1960s.
Remember also that Tomy didn't produce Thomas engines until around 1992 while The Avengers ran from around 1961-1969.
Remember also that Tomy didn't produce Thomas engines until around 1992 while The Avengers ran from around 1961-1969.
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