Product review (5 stars): 40 Pcs Aluminum Foil Square Gas Burner Disposable Bib Liners Covers
Thank you for your fast shipping.  Looks good and it fits 3 of 4 burners perfectly, for my large (4" diameter) burner, I had to cut 4-8 1/4" slits at the center and it fits fine.  This should save me some hard clean up time from spills.