The flashbang grenade is a non-lethal explosive device used to temporarily disorient an enemy's senses without causing permanent injury, designed to momentarily produce a blinding flash of light and an intensely loud "bang". The flash activates all photoreceptor cells in the eye, making vision impossible until the eye restores itself to its normal, unstimulated state. An afterimage will also be visible for a considerable time, impairing the victim's ability to aim with precision. The loud bang causes temporary loss of hearing and disturbs the fluid in the ear, resulting in loss of balance.

Purchased from the USA Barracks, the upgrade enables the use of Flashbang Grenades by Rangers and Green Berets that can cause enemies hit by these non-lethal weapons to lose their ability to fight effectively and forced into submission, allowing USA troops to capture them as prisoners of war (POWs) so they can be interrogated in the Detention Camp for valuable intelligence on enemy positions.

Not all infantry can be made to surrender by Flashbang Grenades, however:

  • Instead of surrendering, Terrorists will wildly run away to random directions before detonating themselves.
  • Due to their fanatical loyalty to the Motherland (particularly to the Leader), Shock Troopers and Shock Trooper Bombardiers would choose death than dishonor by committing suicide with their own weapons instead of surrendering.
  • Heroes cannot be made to surrender due to their special status and training, and would simply be damaged instead.