Avon Protection FM61 CBRN Filter, protects from CB agents, toxins, radioactive hazards and more, designed with bayonet quick fit for use with FM50 mask only. - Dana Safety Supply
Amazon.com: Avon Gas Mask Filter 40mm NATO Standard Size - Longest 20 Year Shelf Life, Military Grade, CBRN, for Full face Respirator mask - Industrial Use, Painting, Chemical Spill, Welding, Gases, Radiation :
FM50 Filter Mount Converter Kit
Avon M50 FM50 Filter Mount Converter Kit, P/N: 601949, 40mm NATO Stanag