Yashuo mask. The production of Yashuo masks has a very strict production management system and the quality is very high. It's a product of Yashuo mask, which has a high reputation. Compared with Yashuo mask, Likang mask has lower cost performance. Therefore, Yashuo mask and Bilikang mask are good. Mask is a sanitary product, which is worn on the nose and mouth to filter the air entering the nose and mouth and prevent harmful gases, smells and droplets from entering and leaving the wearer's nose and mouth. It is made of gauze or paper.