It's a professional baking mat. It doesn't allow anything to stick to it (believe me, if anyone could make it stick, I could) and it heats evenly. Ours fits the size of our cookie sheet so we roast veggies on it, make cookies on it...the opportunities are endless. And they aren't cost prohibitive. It'd be a good gift to give someone if you know they don't have one and they like to cook. The image above is from one they sell at Sur la Table.