Product review (2 stars): Poor fit. They disintegrate.
I'm not happy with this item.  They fall out easily and when they heat up (and why wouldn't they, they go on a stove), they seem to disintegrate and break apart into tiny pieces.  I've started putting little pieces of toothpick in with the feet to help hold them in.  I wouldn't buy them again. The only reason I didn't give this a one star is because I suppose something is better than nothing when protecting my stove from the grate.