I have a question about Roy's Master of Battle Administration

Skimmed the thread, didn't see this asked/answered.

The 2nd part of it says "You gain +2 attack and +2 Defense when fighting monsters that have either the Leader or Duel ability."

If you're fighting a monster with both Leader and Duel do you get 2 bonuses, effective getting a +4 bonus vs. that monster? Or do you just get a single +2 bonus even if they have both abilities?

Thanks in advance.

-Zem