Product review (2 stars): Not For Major Brands!
If by "Universal" the manufacturer meant these knobs fit all gas stoves equally, then they must not fit any.  They certainly didn't fit our major-brand stove and they might not fit yours.  To add insult to injury, after receiving these I found the very same item on closeout at a local store for 99 cents.

Two stars because the knobs are reasonably well-made and come with accessory sleeves to make them not fit in more than one way (or perhaps -- one would hope -- to make them fit some other unknown brands).