Brass knuckle
Wikisimpsons - The Simpsons Wiki
A brass knuckle is a weapon used in hand-to-hand combat.
History[edit]
It is said that Springfield is, apparently, the birth place of the brass knuckle.
Appearances[edit]
Episode – "Lisa Goes Gaga" 
Video game – The Simpsons: Tapped Out (Superheroes 2 collectible)
