There are many types of hard armor, but two materials are particularly useful for the protection of the body. Tensylon and Kevlar are high-tensile materials that provide excellent modulus and shape retention. Polyurea is more expensive than water-proof polyester fabric, but provides excellent protection for the body. For this reason, polyurea hard armor plates are ideal for combat. This article will discuss the differences between the two materials and the pros and cons of each.

The type of hard armor you choose is critical. Depending on your requirements, you may need either Level III or IV protection. Some armor is made from composite materials, while others are made from composites of fiber and metal. This type of armor is usually used by police forces, security guards, and private citizens. However, hard-plate reinforced vests are designed for combat soldiers and police tactical units, and may also be worn by hostage rescue teams.

For NIJ Level 3 and IV tests, manufacturers provide nine armor plates. These are divided into two groups and strapped to a piece of ballistic clay to measure the backface deformation (more). Cartridges are hand-loaded to ensure consistency and accuracy. The backface deformation of each plate must be less than 44mm. NIJ FIT is also available. It will determine whether a hard armor piece is effective in protecting the body.