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A flak jacket or flak vest is a form of body armor. A flak jacket is designed to provide protection from case fragments ("frag") from high explosive weaponry, such as anti-aircraft artillery ("flak" is a German contraction for Fliegerabwehrkanone, "aircraft-defense gun"), grenades fragments, some types of pellets used in shotguns, and other lower-velocity projectiles. It is not designed to protect against bullets fired from most small arms such as rifles or handguns. However, certain flak jackets are able to sustain certain gunshots, depending on the armor, the projectile, the angle at which the shot was fired (an oblique angle for example), and the range from which the shot was fired.