Description:- The Mica Plates Sheets are replacement sheets to use when your microwave oven is arcing around or out of the chamber where the magnetron is located ( small square hole inside the wall of of your microwave oven - a small piece of mica paper covers this chamber ). Your Original mica sheet will be burnt when a bit of food that splatters the inside of the microwave and left on that paper. After a few heatings the food ignited and the paper burned from the food that is attached to it, creating a small hole in the mica paper,this paper will solve your problem well.-Buy this paper, carefully measure the location size in your microwave and cut down to fit in the spot. Most microwaves have a slot or groove of some sort where you position tabs in this paper to fit depends on the brand.