The All-Clad Double Boiler Insert fits all All-Clad 3 or 4 Quart saucepans. It comes with a long handle and is ideal for heating food that needs indirect heat like chocolate or Hollandaise sauce. They are made of non-reactive 18/10 stainless steel and are designed to fit a variety of All-Clad pans. The exteriors have a mirror finish and the interiors are highly polished for a premium look. All-Clad Stainless cookware features a unique tri-ply metal bonding construction which sandwiches a thick core of three separate layers of aluminum between an easy-to-clean, highly polished 18/10 stainless steel cooking surface and a stainless steel exterior. The aluminum core retains heat and evenly distributes it along the bottom and up the sidewalls of the cookware. The stainless interior is non-reactive and cleans easily. The magnetic stainless steel exterior gives the cookware a gleaming finish and is induction compatible. This cookware has a limited lifetime warranty.