Block yellow dust and fine dust with electrostatic filters Allergenic dye,arylamine,pH,formaldehyde test complete Completed skin PATCH test for customer safety Ergonomic 3D design, tri-fold design prevents mask from touching lips, four-layered structure with electrostatic filter, fitted with wire nose piece Supports large and small sizes of each type Gyeongin Regional Food Safety Administration,Ministry of Food and Drug Safety has completed permission