Efficient filtration: Filtering rate above 99% with gases, pollen, droplet, dust, and smog effectively 5 Layers purification: Filament non-woven fabric, flexible moderate thickness, adsorption particle, double layer melt-blown filters Smooth breathing: Flexible insert nosebar ensures optimal sealing between the bridge of the nose and the mask Ergonomic design: Comfortable to wear, low impedance filter material and no odor Secure seal: Soft metal nosebar for best seal between nasal beam and mask