What is ARA?
Many of the freight cars in the Train Miniature line included "A.R.A." in their description.
The American Railway Assocation (A.R.A.) was, "an industry trade group representing railroads in the United States" according
to Wikipedia.org. The A.R.A. first began setting industry standards in 1872 and continued to function until 1934.
The A.R.A. was one of the groups that merged into the American Association of Railroads (A.A.R.), which continues to serve
the industry today.
The reference to a particular model being an "ARA" example means its design in based on plans/standards
set by the American Railway Association and utilized by member railroads in constructing rolling stock that could easily interchange
thanks to similarity that made for good compatibility.