Bullet proof vest or bullet proof vest, usually called bullet proof vest, is a kind of personal armor, which can help absorb the impact force and reduce or prevent the penetration of gun bullets and explosive shrapnel into the human body, and wear it on the bullet proof vest. Torso. The soft vest is made of multi-layer woven fiber or laminated fiber, which can protect the wearer from the small caliber pistol and shot gun shot and small fragments of explosives such as grenades.

These vests are usually fitted with bulletproof plates. Metal or ceramic plates can be used with soft vests to provide additional bullet proof protection, and metal components or tightly woven fiber layers can make soft armor resistant to stabbing and diagonal attacks from knives and similar close range weapons. Soft vests are usually worn by police forces, private citizens at risk of being shot (such as state leaders), security personnel and bodyguards, while rigid vests are mainly worn by combat soldiers, police tactical forces and hostages.

Bulletproof vests can be used in combination with other protective clothing, such as combat helmets. Vests intended for police and military use may also include bullet proof shoulder and side shield armor components, with bomb handlers wearing heavy armor and helmets with face shields and spine protectors.

The ballistic vest uses a very strong fiber layer to "catch" and deform the bullet, making it disc-shaped after bullet shaped, and distributing the force on a large part of the vest fiber. The vest absorbs energy from the deformed bullet and stops it until it completely penetrates the fabric substrate. It may penetrate some layers, but as the bullet deforms, the energy is absorbed by a larger and larger fiber area.

Although vests can prevent bullets from penetrating, vests and wearers can still absorb the impulse of bullets. Even if there is no penetration, the heavy bullet will generate enough force under the impact point, resulting in blunt force. Vest specifications will generally include requirements for penetration resistance and limits on the impact forces transmitted to the body.

On the other hand, some bullets can penetrate the best bullets, but due to the loss of speed and / or their small mass / shape, the damage to the wearer of the bullets is still very small.

Vests designed for bullets can hardly resist the impact of sharp tools (such as knives, arrows or ice picks) or bullets made of non deformable materials (such as materials containing steel core instead of lead). This is because the impact force of these objects is always concentrated in a relatively small area, so that they can penetrate the fiber layer of most bulletproof fabrics. [citation required] in contrast, stab proof vest can better protect sharp tools, but it usually has poor effect on bullets.

Textile vests may add metal (steel or titanium), ceramic or polyethylene sheets to provide additional protection in critical areas. These hard armor plates proved to be effective against all pistol bullets and a range of rifles. These upgraded ballistic vests have become the standard for military use, as bulletproof vests do not work with military rifles. Prison guards and police often wear vests, which are specially designed for cutting-edge weapons and sharp objects. These vests may contain coated and laminated para aramid textile or metal components.