"A hand grenade that creates a large flash of light and a loud sound on detonation."
— Inventory description
— Inventory description - Japanese
The Flash Grenade is a sub-weapon in the Resident Evil 2 remake.
The Flash Grenade stuns any enemy caught within its blast radius, it can be used as a weapon or a defensive item when an enemy grabs the player, however, it will be less effective when counterattacking an enemy's attack.
They can also very briefly stun the player character if they're looking in their direction upon detonation.
Up to three can be stacked in a single slot, making them a very efficient way to disable enemies and a valuable asset.
While it does not provide any real offensive capabilities on its own, its functionality alone makes it a worthy addition to any arsenal with no real enemy in the game being immune to its effect.