Made of pure aluminum for superior heat conductivity and produces consistent evenly browned baked goods every time. These premium pans have a lifetime durability and will never rust. Encapsulated galvanized steel rims prevent warping. Creativity meets natural aluminum sustainability. Voted "Best Baking Sheet," the Baker's Half Sheet is an essential tool in the kitchen you will use in a variety of ways from sheet pan dinners, to baked goods to food prep.