What is this tool thread?

Now i don't have to ask anymore on this forum, what Miller Special Tools are, and used for.
Always thought i had their catalogs.
Haven't seen these in 14 years, since moving into this house.
Forgot that i had them.
Buried deep in a box, way in the back, on the storage shelving.
Jim V.
hemi71x


MILLER TOOL CATALOGS 001 (Small).JPG