3M Particulate Prefilters, 50 per Case - - Amazon.com
3M P100 Respirator Cartridge/Filter 60926, 1 Pair, Helps Protect Against Organic Vapors, Acid Gases, Ammonia Methylamine, Formaldehyde and Particulates: Safety Respirator Cartridges And Filters: Amazon.com: Tools & Home Improvement
3M P95 Respirator Filter 2071, 50 Pairs, Helps Protect Against Oil And Non-Oil Based Particulates: Safety Respirator Cartridges And Filters: Amazon.com: Tools & Home Improvement