Product review (1 stars): Universal is quite an exageration...
These look like very nice knobs...for a stove with much larger D-shafts than mine.  I couldn't find any dimensions on these knobs before buying, so here they are:

There are two adapters for D-shaped shafts. They are both 0.34in wide at widest point.  One is 0.4in deep, the other is 0.61in deep.

My stove is a Kenmore gas range, and has shafts 0.25in in diameter, so these will not fit.