This is for a set of 4 perfect hub caps that were purchased by my wife's Dad (maybe about 1980) but never used.
Might be for a 72 Cutlass.(she remembers that car he had)
I measured one of the caps, it's about 15" wide so I guess it's for a 15" rim(or maybe 14" you will need to measure.)
These were in a closet for the last 45 years. Still in the original box. These are new old stock!
These would be the finishing touch to your mint Oldsmobile restoration project.