This is the best invention. It is a completely nonstick sheet that you put in the bottom of your oven to catch all the drips and crumbs. Just wipe it clean with a sponge or run it through the dishwasher. It is totally reuseable (on both sides!) and oven-safe to 550 degrees. Remove before self-cleaning your oven. Fits all standard ovens and may be trimmed to fit smaller ovens. Made in the USA.