Moldex Smart® Cartridges provide reliable protection against: ORGANIC VAPORS - paint and pesticide, AMMONIA - anhydrous or from livestock confinement, ACID GASES - disinfecting livestock, chlorine, Sulphur dioxide and hydrogen chloride: METHYLAMINE. Pre-filters and retainers are sold separately based on specific application needs. NIOSH approved; TC-23C-1809. 1 Pair.