I have one of my BIG binders full of Oakley print material in front of me today and decided to lay out a small logo and Zero timeline since the generations come up quite often. Now all of this is based on copyright dates on the material and the order it was printed/produced.
1989
Classic Logo
1993
Classic Logo modified [it's slightly sqaushed]
Boxy O Logo
on a gen 1 m brochure
Icon over elliptical O logo
all newer 90s product brochures
Although my 1993 Sub Zero brochures bares the Icon/Ellipse stretch logo all the subs are branded witht he box O logo and the classic on the stem.
1995
Zero brochure featuring 0.1-0.4 only features Icon/Ellipticl logo and all prod bares the boxy logo on bridge and stem. Round lenses.
1996
Zero brochure featuring 0.1-0.6 and the Ps features Icon/Elliptical logo and all prod bares the Elliptical logo on the bridge. No stem shots. 0.1-0.3 have modified larger lenses with a flat edge near the nose piece and the 0.2 and 0.3 have smaller fins.
1996
From the PIM
Product Information Manual folder
Zero page features 0.1-0.6 and only the 0.2P and 0.3P, no 0.2 or 0.3, and shows the 0.4S and 0.4S2. Features Icon/Elliptical logo and all prod bares the Elliptical logo on the bridge and icon on the stem. 0.1-0.3 have modified larger lenses with a flat edge near the nose piece and the 0.2 and 0.3 have smaller fins.
By 1997 the Zero no longer appears in any PIM. On all my athlete portraits
not dated no matter what stretch logo they bare on the printed piece all the E-Wires and Zeros have the boxy logo on both bridge and stem.
During production who knows what may have happened, but it's def created many minor Zero variations for us to nab whether it be a gen 1 small lens 0.1 with the latter gen stem with icon or the larger gen 2 lens with the older boxy logo stems, etc. All depends when Oakley actually changed production on the lens and stems and how long any given part or pair have have sat in a warehouse.