A budget FFP1 moulded respirator that provides reasonable protection against fine dust and particulates. The FFP1 designation means the respirator reduces airborne particles by a factor of 4 when correctly used.
These respirators are designed for short term use (typically 8 hours of continuous use depending on the dust being filtered). Most natural dye workers will intend to use it for occasional, short periods, and it can then be used several times. Replace it when the respirator becomes unclean, dusty or there is any impediment to free flow of air through the mask.
If you require a face mask for longer periods, then the 3M FFP2 dust mask will provide better filtration over a longer timeframe.