These 3M-9920 Dust/Mist And Welding - Fume Respirators are available in various sizes and specifications. With approved protection from metal fumes, used in applications such as welding, soldering, metal cutting or metal pouring where fume hazards may exist. Provides fume - fever relief when welding on galvanized or stainless steel. Also approved for lead dusts and fumes. Easily fits under a welding hood. Exhalation valve improves worker comfort.