The Small Arms Protective Insert (SAPI) is a ceramic trauma plate used by the United States Armed Forces. It was first used in the Interceptor body armor, a ballistic 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.