The fabric mouthpiece is made of three layers of breathable fabric as the authorities recommend it. A pocket is sewn into which a PM2.5 filter can be inserted for extra effect.
The cloth bandage is reusable and therefore not to be thrown away after use. It can be washed at 60 degrees after use, and to change the filter continuously. The filter must be removed before washing. However, it is not a requirement to use the filter.
You can therefore use the mouthpiece again and again.
The mouthpiece is not tested and CE marked as personal protective equipment or medical equipment, and thus does not provide that protection as a protective equipment.