Anyone know what these two little threaded holes were for on the side of a Wayne 515 cylinder base ?

Never noticed them until sandblasted and painted. Some sort of tag attachment?

Thanks

I will have to check mine to see if it has them

Here you go

I know mine does not have that sign.

I have had quite a few Wayne model 515 but these are the only 2 that had these tags .

Thanks for the pics ! Appreciate the info.

What safety feature is the placard referring to?