Generally, there is a triangular mark on the plastic lunch box, which is marked with different numbers from 1 to 7, which represent different materials and also indicate the heat-resistant temperature of the lunch box. Whether the plastic lunch box can be heated, just look at this logo to know.
Among the 7 types, only the plastic lunch box marked with the number 5 can be heated in a microwave oven. When choosing a plastic lunch box, if you see the "5" mark in the triangle at the bottom, this type of plastic lunch box can be heated in a microwave oven, but it is still necessary to choose a brand of plastic lunch box, and the quality is more guaranteed.
Special reminder, if there is no such mark on the lid of the plastic lunch box, be sure to remove the lid when heating. When cleaning this type of plastic lunch box, do not use sharp objects to prevent scratching the plastic surface, which will produce bad chemicals when heated.
