Flak jacket

A flak jacket or flak vest is a form of body armor designed to provide protection from case fragments ("frag") from high explosive weaponry, such as anti-aircraft artillery ("flak" a German contraction for "Fliegerabwehrkanone" (aircraft-defense gun)), grenades, some round shot used in shotguns and land mines and other lower-velocity projectiles. It is not designed to protect against bullets fired from small-arms such as rifles or handguns. However, certain flak jackets are able to sustain certain gunshots, dependent on the armor, the gun, and the distance that the bullet has travelled.

The term "flak jacket" is often colloquially applied to newer body armor featuring protection against small arms projectiles, but the original usage predated the existence of functional bulletproof vests and the two are not interchangeable in performance.

Anecdotes describing garments designed to protect the wearer from penetrating weapons can be found far back into recorded history. Two types of protective garment from the American Civil War in the 1860s had a basic design similar to the flak jacket or ballistic armor of modern times in that solid plates were used as the main ballistic protection. The "Soldiers' Bullet Proof Vest" was manufactured by the G. & D. Cook & Company of New Haven, Connecticut. It consisted of two pieces of steel inserted into the pockets of a regular black military vest. Versions for infantry weighed 3 ½ pounds while a version for cavalry and artillery weighed 7 pounds. They sold for $5-$7. A more medieval-looking type of armor was made by the Atwater Armor Company, also of New Haven. It consisted of four large plates of steel held on the body by broad metal hooks over the shoulders and a belt around the waist. The Atwater vest was heavier than the Cook models and cost about twice as much.

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