forehead protector
A piece of protective gear for the forehead. May be in the form of a metal plate attached to a cloth headband (as in Naruto, where most ninja wear such headgear with their village's symbol engraved on it), an entirely metal headband, or even a metal piece on the forehead which seemingly isn't held in place by anything at all (i.e. Leona in League of Legends).
Examples
