The stainless steel steamer is made of steel, magnetic and non-magnetic. Many people have been misled that magnetic materials are easier to rust than non-magnetic materials. This understanding is too general. In fact, magnetic materials are not equal to the quality of rust prevention. The main thing depends on the material of steel. The non-magnetic materials are mainly 201 and 304 materials, and the magnetic materials are mainly 430 and YH21CT. The 430 stainless steel is slightly stronger than the non-magnetic 201 stainless steel. The second is YH21CT. 304 stainless steel is a non-magnetic stainless steel that adopts American standards. It is austenitic, used in medium and high-grade steamer.