RFH 355nm UV Laser marks plastic shells of Midea electric appliances In order to cooperate with the development and operation of the new model, Midea has worked hard on the details. In order to create a better plastic housing for home appliances, it has introduced a RFH high-frequency ultraviolet laser to mark the plastic housing. Whether it is small household appliances such as rice cookers and hair dryers, or large household appliances such as fans, refrigerators, washing machines, and air conditioners, UV lasers can accurately mark the plastic surface.