4. First generation of plastic diaphragm rings (ivory color), whose mounting screws were recessed into the plastic, to be flush with the ring's surface, ca. 1966 to 1980
5. Same as above, but with white instead of ivory-colored rings, since ca. 1980
6. Same as above, but diaphragm mounting ring screws no longer recessed, since ca. mid 1980s
If I understood correctly from this ...
My capsule has ivory diaphragm ring and mounting screws were recessed into the plastic. It says number 2 ... after that it was 1972
maybe I'm wrong because I ask you ...
As far as I can see in the picture, the screws are highlighted above the plastic and the ring is white, shouldn't my capsule look like that if it was 1992 ...