Multi Purpose Respirator, Flexible Facepiece For Better Seal, Low Profil Cartridges For Unobstructed View, Approved For 42CFRS4 Regulation As Well As P100 Filter Class, Approved For Ammonia, Organic Vapors, Chlorine, Hydrogen Chloride, Chlorine Dioxide, Sulphur Dioxide, Hydrogen Sulfide For Escape Only, Formaldehyde, Hydrogen Fluoride, & Methylamine Gases, Uses MSA #817667, True Value #105-684, Multi Purpose Replacement Cartridge.