A “flash hider” is a device that is attached to the muzzle of a firearm that is designed to reduce or eliminate the visible flash that is produced when the gun is fired. This visible flash is caused by burning gases as they exit the muzzle of the gun, and can often give away the position of the shooter. Flash hiders come in a variety of designs, but all work to some degree at hiding the flash produced by firearms.
Robert Edited answer June 29, 2022