Cartridge, NIOSH Rating Chlorine (CL), Chlorine Dioxide (CD), Hydrogen Chloride (HC), Hydrogen Sulfide (HS), Organic Vapor (OV), Sulfur Dioxide (SD), Yellow, Compatible with Brand and Series MSA Comfo Twin-Cartridge Series, Respirator Cartridge Type Air Purifying Respirator, Respirator Connection Type Threaded, Package Quantity 10. This item has been restricted from sale in the following state (s): []