Product review (1 stars): Pooor quality control!
Wish I could give less than a star.  I'd bought replacement knobs before that look as if the same manufacturer.  But quality control on these terrible!  Got gasket/ring on burner knob stem of stove but then can't fit knob on gasket!  Now I can't get the gasket off to put previous knobs back on.  Yuck!  My fault I waited too long to return.