1966 US Army Field Manual FM 21-40 Chemical Biological Nuclear Defense Vietnam Era

Original US Army Field Manual FM 21-40 titled Chemical, Biological, and Nuclear Defense, dated September 1966. Complete at 93 pages and printed in the standard three-hole punched format for field binders. Covers CBRN defensive procedures, protective equipment, decontamination, and field survival, with period illustrations including gas masks, atropine injectors, and related gear. Condition is very good with a clean cover, light age toning, and strong staples; pages are intact and very readable. Solid Vietnam-era piece that displays well and fits nicely into any Cold War collection.