I own a pair of Oakley Flak Jacket XLJ sunglasses, and use them practically every day.  Despite being careful with them, after a couple of years there were a couple of distracting scratches on the lenses.  Replacement lenses from Oakley are a stout $90, so I turned to Amazon to see if a more reasonably priced alternative existed.

These lenses do not fit my Flak Jacket XLJ frames well at all. They are in danger of inadvertently falling out of the frames, not a good thing.

I would not recommend these lenses.