All Clad’s Copper Core cookware features a patented 5-ply bonded construction. The alternating layers of stainless steel and aluminum have a copper core, allowing for ultimate temperature control and precision. The copper core with the stainless-steel exterior provides the benefits of cooking with copper without the maintenance. Features an exposed copper cutout on the side of the pan. Compatible with gas, electric, induction, and ceramic stovetops. Oven/Broiler safe to 600°F (without lids). Bonded, Engineered, & Assembled in the USA. 18/10 stainless steel cooking surface.