Body armor is a necessity for police and military personnel.
A military flak vest or body armor is considered part of the uniform for many police departments and for members of the military, like soldiers, sailors, marines and airmen. Non-police and non-military individuals may buy bulletproof vests for their own use.
At one time, bulletproof vests were almost exclusively made of Kevlar, a synthetic material, and often reinforced with ceramic or metal plates for greater protection. These vests were quite heavy. Many wearers valued vests according to their weight. Improved technology has allowed some lighter-weight materials such as Spectra to be used in bulletproof vests.
The National Institute of Justice inspects and tests body armor for effectiveness. Vests are rated for types and velocities of bullets and knives they will deflect or absorb. Some vests are compact, covering only the torso to the waist. Others provide more coverage, protecting the shoulders, neck, and groin. Additional products for arms and legs are available.
Bulletproof vests have a limited lifespan of a few years if they are worn daily. However, used body armor in excellent condition is widely available and more affordable than new armor. New military-style vests sell for as much as $1,600, while other styles cost just a few hundred dollars. Used vests can be found for as little as $100.