These filters and cartridges are compatible with Honeywell North 5400, 5500, 7600, and 7700 reusable respirators. - Particulate filters and vapor cartridges are NIOSH-rated and installed in reusable half-mask or full-face respirators to filter out airborne contaminants. - They are selected based on the environment and type of respiratory hazards that need to be filtered. - They can be changed out when they become dirty or when the type of contaminant changes. -Filters and cartridges are compatible with a specific brand and mask model. NIOSH Rating / P100 Color Code / Magenta Respirator Cartridge Type / Air Purifying Respirator Respirator Connection Type / Threaded Series / N Standards / NIOSH