Uni-sorb™ cartridge with permanently attached P100 pre-filter. This cartridge protects against: organic vapors, acid gases (sulphur dioxide, chlorine or chlorine dioxide, hydrogen chloride), ammonia or formaldehyde, plus chemicals that contain an oil mist. For use with the Opti-Fit™, Valuair® Plus, Max™ and Premier® respirators from Survivair®. NIOSH Approval No. TC-23C/84A. Box of 4.