Calphalon Tri-Ply Copper unites centuries-old culinary tradition with premium performance and distinctive style. Featuring graceful curves and a stunning combination of expertly finished, tri-bonded metals, this collection is as beautiful as it is hard-working. A brushed copper exterior and aluminum inner core combine for superior conductivity and precise cooking control for spectacular results. Fine-satin, brushed stainless steel interior won't react with foods and won't tarnish or change colors even when cooking acidic foods like tomato sauce. Highly conductive copper and aluminum combine to provide superior heat conductivity, precise cooking control and excellent browning.