3M - 5N11 Filter - Particulate Air. 3M Half Face piece Reusable Respirators offer the user comfort and convenience coupled with the cost savings of a reusable respirator. Reusable - just dispose of the cartridge and filters when used to capacity. The swept back design of the cartridges improves balance and visibility. Can be disassembled, cleaned and reused. Very light-weight. Easy to adjust head straps. NIOSH approved for use against particulates and a variety of gases and vapors at concentrations up to 10 times the exposure limit, when used with approved and properly selected cartridges and/or filters.