The original insulated bakeware. Premium insulated bakeware. 100% aluminum construction - guaranteed not to rust. No burning - guaranteed. 2 heavy-weight aluminum sheets surround a layer of air. The air reduces the temperature of the metal that comes in contact with the food. This ensures that food is heated evenly all around. Cakes bake more evenly and don't dome in the center, cookies don't burn, and baked goods are moister. Dishwasher safe. Nonstick interior and natural aluminum exterior. Size: 15-3/4".