This 3 qt. double boiler insert easily nests in All-Clad sauce pans and casseroles with an 8 inch diameter for preparing items on indirect heat. This is particularly ideal for melting chocolates or preparing cream based desserts and sauces. It can also be used to reheat foods that may change in consistency or flavor when applied to direct heat. Durable heavy-gauge stainless construction. Sits deep into the pan. Fits All-Clad 3-quart sauce pans, 4-quart sauce pans, 3-quart casseroles and 4-quart casseroles. Long stick handle stays cool on the cooktop. Lifetime warranty.