This iris-ring is called in Germany since over 100 years Universalanschraubring or Universal-Objektivring.

One example in ICA-Hauptkatalog Dresden 1912: sizes - greatest (littelst) size for optics 53 (20), 60 (20), 80 (25), 120mm (40mm)

One example in Mail order catalogue Central Camera Company, Chikago 1935, page 98, Iris Lens Flanges
No. 1 for lenses 4-10 to 2 4-10'' Dia. up to
No. 4 for lenses 2 -to 4 3/4 '' Dia. - this costs Dollar 9.60 (not today)

In France (and in Germany) it was in sale up to 1963: Central Ohoto - France Photo ICA - Photo-Cine-Stock
Catalogue gros 1963, page 54 Rondelle Universelle in two sizes
Ouverture de 15 a 60 mm 61,40 Francs
Ouverture de 25 a 100 mm 102,23 Francs

They were deliverable together mounted on a sync. shutter 1/25 sec. from Gitzo with free diameter 59 or 74 mm. Thuch a piece I have on my Kardan-Color, I found in Bievres, Paris on the famous fleemarket. Good old days, there had been EVERYTHING!!