3M True US-Mil-Spec FR-M40-10 Small Chem-Bio/NBC Protective Gas Mask. Brand New – 3M Factory Sealed Box – CBRN Approved In USA. The M-40 Full Facepiece has been used for years by U. Armed Forces all around the world. This facepiece has been NIOSH-approved with the 3MT Cartridge FR-C2A1 or 3MT Cartridge FR-64 for acid gases (including chlorine), CN, CS, and P100 particulate filter. The FR-M40 full facepiece respirator has the capability to mount a single 40mm DIN threaded cartridge on either the right or left side. Paul, MN – Made In USA. Mfr part number: (Facepiece: 5-1-1001-20). US Government Contract #: (M40 was the primary US Military Gas Mask System). AGM / Approved Gas Masks – Trusted suppliers of personal protective equipment to military, law enforcement & civilian users since 2001. Our customers include 1000’s of major police departments, government agencies, fortune 500 companies, all the major media outlets & governments worldwide! >see for yourself, our feedback says it all! >99.6% of orders to be exact!