The Interceptor Multi-Threat Body Armor System introduced the idea of small-arms protective inserts (SAPI) -- ceramic plates slipped into body armor pockets -- that dramatically increased the vest's protective value. While a Kevlar vest protects against pistol rounds and shrapnel, with the added SAPI plates even rifle rounds can be reduced to non-lethal effect. After their successful use with Interceptor, the SAPI plates (and their enhanced version ESAPI) continued to be used with new generations of tactical vests.

Vern Clifford, quality assurance specialist for Defense Contract Management Agency, Wichita, KS, testing SAPI plates in the work area of the Wichita plant of vendor Leading Technology Composites, 2006
Vern Clifford, quality assurance specialist for Defense Contract Management Agency, Wichita, KS, testing SAPI plates in the work area of the Wichita plant of vendor Leading Technology Composites, 2006.

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Small Arms Protective Insert (SAPI) Ballistic Protection Plates

Interceptor Body Armor SAPI

By itself, the body armor vest protects the user from shrapnel and 9-mm pistol rounds. When the protective Small Arms Protective Inserts (SAPI) are added, the system acts as a ballistic barrier to 7.62-mm rifle ammunition. The same plates are used with Interceptor Body Armor Outer Tactical Vest (OTV), and further developments in vests, such as the Improved Outer Tactical Vest (IOTV), the USMC Modular Tactical Vest (MTV) and the USMC Scalable Plate Carrier (SPC).

The Small Arms Protective Insert (SAPI) is made of a boron carbide or silicon carbide ceramic with a Spectra backing, a material significantly stronger than Kevlar. It stops, shatters and catches any fragments up to a 7.62 mm round with a muzzle velocity of 2,750 feet per second. The four pound high-technology plates cost approximately $350 each to produce, a considerable cost reduction achieved by Army-industry cooperation.

A major upgrade effort to make Interceptor Body Armor with SAPI standard issue was completed in early 2004. Between 2.0 and 2.5 million SAPI plates were issued, utilizing multiple contractors producing 25,000 sets per month. Additional protection was added for upper arm and underarm areas in the form of the Deltoid and Axillary Protector (DAP), and the Enhanced Side Ballistic Insert (ESBI) plates.

Enhanced Small Arms Protective Insert (ESAPI) Front/Back Plates
Enhanced Small Arms Protective Insert (ESAPI)
Front/Back Plates");?>

Enhanced Small Arms Protective Insert (ESAPI)

The Interceptor SAPI plates were replaced by ESAPI plates (Enhanced Small Arms Protective Insert), beginning in May 2005 for the U.S. Army, Marine Corps, and other users. At a 50% increase in cost (about $600 per plate) vs SAPI, ESAPI is a thicker boron carbide ceramic plate backed by multiple layers of a non-woven ballistic fabric film (unidirectional polyethylene material) that provides protection from armor piercing rounds and rifle-fired 5.56mm and 7.62mm rounds.

Other improved SAPI plates have been in development for future use, including the Improved Small Arms Protective Insert (ISAPI), and X Small Arms Protective Insert (XSAPI). The higher protection level silicon carbide XSAPI has the potential for use if threats are experienced that exceed the protection capability of ESAPI.

The Lightweight Ceramic Armor (LCA) program seeks to reduce the weight of armor plates while maintaining the protection level of ESAPI. Since vests and carriers can be used with any plates that meet dimensional requirements, it would be possible to upgrade equipment in the field when better plates are available.

SAPI / ESAPI Ballistic Plates Weight and NSN Information

Each body armor vest uses at least two inserts, each weighs 4 pounds on average. ESAPI adds about one pound to the weight of SAPI Interceptor. ESAPI plates weigh 13 pounds for the large size.

The SAPI and ESAPI plates for the front and back of the vest are available in five sizes from x-small to x-large, tabulated here with NSNs. All size inserts are interchangeable between front and back pockets of the OTV

X-Small 8470-01-497-8701 8470-01-520-7360
Small 8470-01-497-8709 8470-01-520-7370
Medium 8470-01-497-8710 8470-01-520-7373
Large 8470-01-497-8712 8470-01-520-7382
X-large 8470-01-497-8714 8470-01-520-7385

Interceptor Body Armor Side SAPI
Interceptor Body Armor Side SAPI.

The 2.3 pound 6x8 inch Enhanced Side Ballistic Insert (ESBI) (ie, Side SAPI) is one size, NSN 8470-01-534-0760 (two required per vest). Also known as Enhanced Side Small Arms Ballistic Insert (E-SSAPI). An X-Small SAPI or ESAPI front/rear plate can be substituted if permitted by the unit commander.

To fit properly, the front and back inserts should be the same size as the vest. That is, if you wear a medium vest, order the medium plate. The exception is if you wear an xx-, xxx- or xxxx-large vest. For vests larger than X-large, use the X-large inserts.

The Use and Care Manual for the Outer Tactical Vest (OTV) and Small Arms Protective Insert (SAPI) plates is TM 10647A-12.

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