The Harkonnen II is an extremely heavy and destructive weapons system designed for and used by Seras Victoria with the exclusive purpose of defending Hellsing Organization headquarters. It had a gross weight of 345kg and sported a pair of 30mm auto cannons belt-fed from two large ammunition boxes carried on her back. Its maximum range was 4 kilometers (4000 meters), and was used to destroy a barrage of Millennium's missiles in midair and even shoot down one of their airships; the system was used to great effect against Zorin Blitz's invasion force, considerably thinning her forces and prompting a ground invasion.
For additional firepower, the pair of cannons could double as a grenade launcher, launching two of the explosive incendiary grenades for wide-area field dominance "Vladimir," one from each barrel. Due to Seras' vampire strength, she could move around with the system with relative ease after she discarded the massive ammo boxes.