[AnAmericanMother]

Thanks. In this photo it's clear that it's not a screw top.

Other thread here.

[Old Professer]

To produce this cup requires the use of precision punches and dies, especially to hold the fit against the upset ring that serves as a stop seal.

While a similar handworked version would require many hours of labor and could probably be accomplished, the obvious similarity of this photo cup and a much more modern one produced since the machine age is undeniable.

Are we being had here?