Calphalon Tri Ply Copper 4 qt Chef's Casserole with Lid Copper exterior and aluminum inner core combine for superior conductivity and precise cooking control Non-reactive stainless steel interior offers the reflective cooking surface many chefs prefer. Brushed copper exterior complements both traditional and contemporary dcor. Flared rims are more durable, which make pouring neat and easy. Oven and broiler safe for maximum versatility in the kitchen Lifetime Warranty