NIOSH-approved for protection against: Chloroacetophenone (CN) Chlorobenzylidene (CS) P100 particulate efficiency level Particulates Gas mask canisters filter airborne contaminants for CBRN (chemical, biological, radiological, and nuclear) environments Designed to protect against one or more specific hazards and are used with compatible headgear Canisters can be dual-mounted on the gas mask to allow weapon firing from either shoulder