You can't go crazy for a mask because of poor breathing. You need a mask with a fresh fabric, which allows you to breathe properly, which can be worn even for hours without disturbing you. Furthermore, it must be washable and reusable in order not to have too many continuous re-purchase expenses. Here it is: the TZ 27 mask with sanitized fabric of which we provide the document. When you wear it you don't realize you have it. You breathe very well, you have a fresh feeling. That's why so many customers keep ordering it. It is a single color, light gray and we know it cannot please everyone, but when you wear it you change your mind, because first of all there is comfort and convenience.