Cartridges provide respiratory protection against gases and vapors by using sorbents to purify the inhaled air. Cartridges without particulate filters do not remove dust, fibers and other particles. 3M offers wide selection of cartridges to provide respiratory protection against a range of industrial air contaminants. The outer casings are made from a durable, lightweight material, and color coded for quick and easy identification. The cartridges are approved for use with both 6000/7000 series half mask and full facepiece respirators. All cartridges are NIOSH approved, meet 42 CFR 84 requirements, when used with 3M air-purifying respirators. 2 cartridges per package. 30 packages per case. Sold by the package.