Make mega batches of cookies and bars with this extra large sheet pan. Fits all standard size ovens. 35 percent larger surface than the half sheet! Our commercial-duty Naturals Bakeware is made of even-heating, rust-proof aluminum and features a galvanized steel reinforcement around the rims for added strength. Bakers agree that aluminum bakes best. Hand-wash cleaning only. Made in the USA. Nylon, wood, or silicone utensils are recommended. Metal utensils and scouring pads may scratch natural aluminum pans, but will not affect baking performance. Pan exterior dimensions 21 x 15 x 1 inches and Inner dimension L - 19.50 W - 13.50 H - 1.00 inches.Use & Care: 1. Before initial use and after subsequent uses, hand wash with warm, soapy water. 2. Dishwasher use is not advised, as discoloration will occur due to the cleaning agents used in automatic dishwasher detergent. This discoloration is merely cosmetic and will not affect baking properties or safety of the pan. 3. Natural aluminum pans work well with parchment paper, silicone baking mats, and also traditional butter or shortening and flour methods. When roasting savory foods such as vegetables, butter or cooking oil work well. 4. Nylon, wood, or silicone utensils are recommended. Metal utensils and scouring pads may scratch natural aluminum pans, but will not affect baking performance.