It can naturally remove humidity in the air using a silica gel. It is semi-permanent and reusable by drying in the sunlight, microwave, or hair drier unlike the conventional disposable dehumidifying agent. Because the case is harmless to the human body and heat-resistant it can be dried in the microwave. As the silica gel is sealed with the heat-resistant nonwoven fabric and a special thread it is free from damage in the heat