Designed to fit most Calphalon straight-walled 2.5 quart sauce pans, the Calphalon 2-qt. double boiler insert is made of stainless steel polished to a beautiful mirror finish. The Calphalon double boiler is ideal for gently heating delicate sauces such as hollandaise, melting cheese or chocolate, or preparing polenta. It goes safely into the dishwasher and carries a lifetime warranty. Not compatible with 2.5-quart shallow or curved wall pans.