Does anyone know if the SI Lens kits for the M-Frame and Half jackets will fit in the regular frames? Having the higher safety ratings, does that mean the lenses are cut thicker for the SI frames? Thanks.

They should, I know for a fact that the M-frame lenses are notched at the top when necessary to accomodate the frame, and as far as I know, SI frames are just a colorway thing and not thicker or reinforced in any way.

HJ's are just the standard one. The ANSI M Frame, is just the clip re-enforced lens as far as I know. Don't use the clip, and then you can use any other lens.

Dann is right as always. I've compared the M Frame lenses side by side and the only difference is notch for the clip. Thickness is the same and the frames themselves are also identical so any lens will fit. The clip simply makes it harder for an impact to dislodge the lens from the frame.

I personally don't like the clip since it makes me go a little cross eyed.