The Shellback Tactical Level IIIA Model CLCIIIA Flap Sac Soft Armor Insert is specifically designed to fit the Flap Sac and Flap Sac 2.0. This ballistic package is NIJ 0101.06 certified, lightweight and provides ballistic protection against common handgun rounds. This insert slides directly into the rear pocket located on the hook side of the Flap Sac.