The 35mm F2

Eight Elements in Six Groups
Weight: 285g (10 oz)
Diagonal Angle of View: 62 Degrees
Minimum Aperture: F16
Filter Size: 52mm
Version 1) Introduced August 1962; Serial numbers: 102105 to 110999; Lens coating light yellow or pale amber; had an almost ungrippable aperture ring; lens data on outside of filter ring; ceased production March 1967
Version 2) Introduced December 1965 with improvements to optical design and lens coating technology (i.e. early but not denoted multi-coating); Onset serial number: 690101
Version 3) Introduced September 1973 with further improvements to multi-coating design denoted by "C" in the engraved lens data; Serial numbers from 835001 to 871141
Version 4) First "Modern Look" 35mm F2; Design incorporation of RIFR; Subtle improvements to optical formulation allowed extension of F-stop range to F22; Onset serial number: 880001
Version 5) First "AI" version; Double row of F numbers on F-stop ring;
Version 6; AIS version; Onset serial number: 105002