This half facepiece reusable respirator offers reliable and convenient respiratory protection and is suitable for many situations, helping provide protection against particulates and a wide variety of gases and vapors according to NIOSH approvals. Compatible and convenient respiratory protection. Half facepiece reusable respirator. Offers reliable, convenient respiratory protection when combined with particulate filters or cartridges (such as organic vapor/acid gas cartridges) or dual airline system. Sold as a Case of 24. Size Large. (Filters & Cartridges not included) NIOSH, a Federal government regulatory agency, has tested and approved the 6000 Series Half Facepiece with 3M cartridges, filters or supplied air systems. The 6000 Series is NIOSH approved for negative-pressure air purifying and positive-pressure dual airline applications. This half facepiece respirator may be used with 3MTM Cartridge 6000 Series; 3MTM Filters 2000, 2200, 7000 or 5000 Series; or 3MTM Dual Airline Systems against a variety of gases, vapors, and particulate hazards according to NIOSH approvals.