Calphalon Classic Bakeware 14-by-16-Inch Nonstick Large Insulated Cookie Sheet Large, nonstick cookie sheet made of heavy-gauge, aluminized steel Heavy-duty construction means no twisting or warping Insulated layers promote moist, chewy results every time Oven safe to 450 degrees F; not broiler safe; not dishwasher safe Measures 14 by 16 inches; lifetime warranty