2 Pack, Multi Purpose Replacement Cartridge, Fits Model 807669, Is The Most Widely Approved On The Market, Approved For P100 Filter Class As Well As Ammonia, Organic Vapors, Chlorine, Hydrogen Chloride, Chlorine Dioxide, Sulphur Dioxide, Hydrogen Sulfide For Escape Only, Formaldehyde, Hydrogen Flouride & Methylamine Gases, Used In MSA #817663, True Value #104-367.