Help Ring ID. Do all NF rings have a digit stamp?

[tctt3]

I'm trying to attach pics. I have 3 sets, one in the package, of NF rings. One set looks identical to those but taller, the other looks identical but is steel. They don't have the height stamped on the bottom though. Could these be older NF rings before a stamp?? Or, something else? I don't need them, but want to know what they are 100% before I post them. Thanks

 

[tctt3]

 

[tctt3]