Very likely an HO model. I had that engine or a similar one as a kid. The other video linked at the bottom of the article[1] shows a historical photo of #722 w

Very likely an HO model. I had that engine or a similar one as a kid. The other video linked at the bottom of the article[1] shows a historical photo of #722 which was the same model locomotive. [1] https://vimeo.com/176065209 https://vimeo.com/176065209