When Erika Eleniak and Steven Segal walk through the battleship and talk about her rule, ie. not killing people and not dating musicians, Steven has different types of the SMG MP5 in his hands. He changes from MP5 to MP5K and back in the blink of an eye.
Early on in the film an officer shows a copy of Playboy magazine to a crewman. Erika Eleniak was the centerfold in that issue of Playboy.