Why brass knuckles do 0 additional damage in Vampire: The Requiem 2nd Edition?

I’ve been creating a character and thought that it was cool for her to have brass knuckles to fight, but then I’ve seen that in the Core book (pg. 180) says that brass knuckles deal 0 damage (appart from the damage that you deal with raw brawl. In the Chronicles of Darkness 2nd Edition core book says the same.

Is this an errata, or there’s something I’m missing?