3M� Secure Click� Particulate Filter P3 R D3138 is CE approved for environments containing certain particles. Our filter can also be used for nuisance level organic vapour relief and for ozone protection up to 10 x WEL. New dual flow cartridges and filters allow for easier breathing, Protects against particulates with nuisance level organic vapour/acid gas relief, Protection against ozone up to 10 x Workplace Exposure Limit, Quick, simple connection. Simply align the connections and push until you hear a click, Use with 3M� Secure Click� Reusable Respirators 800 Series, Swept-back design allows an enhanced field of view and comfort, Use for protection in hazardous environments, CE approved 1 BOX = 20 FILTERS (NOT PAIRS)