Superdome is the term used to describe the original crystal used in the sea dweller, not to be confused with the modern replacement available for the vintage (plastic crystal) sea dweller,
The pic here shows the superdome in the foreground and the replacement in the background..
The crystal of the EZM is similar in shape if memory serves me correctly.

As to my work watch, this is what is started out as..

Factory service luminova dial and hands and bezel insert, non superdome crystal..a project watch which came out just right..a great beater, seeing as it is not factory original, heck it has already taken both oil stain and motor oil baths..
Cheers,
D