Fat Daddio's Cookie Sheet Pan is made with 14-gauge anodized aluminum. Anodizing completely seals the aluminum, making a smooth scratch-resistant surface, and ensuring there is no cross-contamination or leaching of aluminum into foods. Anodized aluminum is also non-reactive with acidic and dairy ingredients. Fat Daddio's anodized aluminum bakeware, baking pans and cake pans are precision engineered to offer excellent baking performance, even heat distribution, and durability. Bake your best with Fat Daddio's bakeware. Dishwasher safe. Lifetime warranty. Available as 10 or 14-gauge.