Vivitar
The historic and innovative first version of the Vivitar Series 1 70-210mm went on sale in 1974, and was a significant step forward in the capabilities of a third party zoom, especially its close focus mode. Made by Kino Optical (Kiron) - 22xxxx serials. The third number in the serial indicates the year of manufacture: 4=1974, 5=1975, 6= ....0=1980, 1=1981.
Can be found in all the mounts of the era including PK and M42. But this was pre-PKA so doesn't exist in PKA. Replaced c. 1981 by the Tokina made 37xxxx version.
Early versions don't have VMC "Vivitar Multi Coating" on the nameplate, and there were small structural revisions over the production period
