Ceramic plate

A trauma plate, also known as a trauma pack, is a plate that is an add-on component/insert to a ballistic vest. Its primary purpose is to absorb and disrupt the kinetic energy of a bullet impact and reduce the blunt trauma transferred to the wearer of the vest. Trauma plates typically enhance the ballistic value (how "bulletproof" it is) of the part of the vest that they are positioned behind.

Trauma plates are most commonly found in a pocket in front of the ballistic panel of a vest and positioned in the center of the chest. Some vests feature plate pockets in the back of the vest as well as the front. Some advanced tactical and demolition vests accommodate a multitude of trauma plates. Unique, high-end vests, like Dragon Skin, do away with traditional trauma plates and integrate interlinked, miniature trauma plates as scale mail, to significantly enhance overall ballistic rating, while maintaining flexibility.

Trauma plates can be found in a variety of sizes and shapes. The most common shapes are rectangle, rounded rectangle and irregular hexagon.

In concealed vests (vests worn under a shirt), the trauma plates are most commonly 5″ × 8″, with variants including 5″ × 7″, 5″ × 9″, 6″ × 8″, and 6″ × 9″. Thickness (depth) varies based on material and application but rarely exceed 1/4″.

In tactical vests, worn as outerwear, the trauma plates are most commonly 10″ × 12″ with some variation depending on the vest. Thickness varies, depending on material and application, but rarely approaches 1/2″.

In specialized/military-grade vests, a considerable portion of the vest is made up of rigid, trauma-plate like inserts. Since they are an essential part of the vest, they are NOT typically considered the same as trauma plates and are typically referred to as inserts, much like the aramid ballistic inserts found in concealed, duty, and tactical vests. SAPI vests are an example of this type of vest. In most SAPI based vests/carriers, the outer vest is made out of and lined with aramid material is made to carry multiple ballistic inserts, typically made out of ceramics. These inserts are shaped to fit the carrier and have sizes that vary depending on the size and shape of the vest.

Most trauma plates are made of a combination of materials. The following categories denote the primary material used in different plate packages.

A ceramic is a non-metallic, inorganic material—like glass, but much stronger and consisting of a variety of possible materials. Ceramic plates, typically composed of boron carbide or near variants, are very popular in military application. These materials offer very high ballistic value. However, they do not do very well at dispersing blunt trauma. As a result they are often backed with materials like aramid fabrics, high density plastics, and/or metals. The advantages of ceramic armor is that they are not only lighter than metals, but much harder as well, which enables them to deform most penetrators.

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Wikipedia