It can also used to be placed in the refrigerator for refrigeration, which is convenient, practical and necessary for home. It can be used to put in the microwave oven to heat steamer stuffed buns, steamed buns, etc without water loss. Material: plastic ,Food grade PP material is environmentally friendly and safe. How to use: Put frozen food or food in the steamer, add appropriate amount of hot water to the steamer chassis, cover the lid and heat it for 8 minutes. After the microwave oven stops working, take it out and eat it.