The
Small Arms Protective Insert (
SAPI) is a
ceramic plate fielded by the
US military. It was first used in the
Interceptor body armor, a
bullet resistant vest. It is now also used in the
Improved Outer Tactical Vest as well as the
Modular Tactical Vest, in addition to commercially available "plate carriers". The
kevlar Interceptor vest itself is designed to stop projectiles up to and including
9x19mm Parabellum submachine gun rounds, in addition to fragmentation. To protect against higher velocity
rifle rounds, SAPI plates are needed.
In May 2005, the US military began replacing the standard Small Arms Protective Insert plates with the Enhanced Small Arms Protective Insert (ESAPI).[1][2] An ESAPI provides protection from armor piercing bullets, but costs about $600 per plate, 50% more than SAPI plates.[2] They are produced by Ceradyne, BAE Systems, and ArmorWorks Enterprises.[3]
A call for a next generation plate, to stop even greater velocity threats that the ESAPI plate has been issued by the US Army.[3] They have specifically allowed scalar or flexible systems, and are also calling for greater coverage, with less than a pound of additional weight.[4][5]
The standard plate for the Interceptor body armor is made of boron carbide or silicon carbide ceramic.[1]New ESAPI plates are also made of boron carbide.[6] A SAPI is able to stop up to three rifle bullets of a caliber up to 7.62x51mm NATO M80 ball and of a muzzle velocity up to 838 m/s (2,750 ft/s). The ceramic plate is backed with a shield made of Spectra, a material up to 40% stronger than Kevlar.[1]
