Premium Ilsa Heat Diffuser - 8 1/4 Inch Black Stove Protector (2-Pack) - Protects Countertops from Heat Damage for Gas & Electric Stoves

I have both sizes of the Ilsa diffuser- the 8.25 and the 7 inch. Although I already have solid electric elements on my 'antique' canning stove, I wanted a bit more protection from direct heat for my Pillivuyt cookware. I don't cook foods quickly and prefer to cook them on a lower heat very slowly. These do take a few minutes to heat up but if you're patient chef, you won't mind. My pillivuyt cookware performs exceptionally well with these. I also have a Tagine that performs well with these. I usually turn the stove on and let the diffuser warm while I'm preparing food.I wanted to note that while the 7" fits like a glove over my small stove element, the 8.25 does not and sits on top of the large element creating a slight air space between heat source and diffuser (The small 7" surface makes direct contact with the solid element on my stove) Despite the 8.5 inch larger size, the bottom rim that it sits on is the exact same size as the 7 inch. The only difference is that the larger size has an additional rim on the surface that extends beyond the 7" bottom rim. The overall size is the same diameter of my large element but again, it sits on top of the element and the top surface does not make direct contact with the existing element which is fine and that's what they are meant to do. It's just that I had hoped they would because I was trying to disguise the older ( unattractive) elements on my stove. Hope that makes sense. I'm not exactly certain why they put a hole in the center of the large diffuser. maybe someone else could answer that.These are also great for keeping food warm without burning.