The F5L-class was a type of Klingon Empire starship, a bird of prey created as a subclass of the Qud-class frigate in Klingon Defense Force service in the 23rd century. This Klingon bird-of-prey subclass was designed to serve as a frigate leader, with capacity to serve as a command ship in fleet actions, built on the standard QuD hull spaceframe. Ships of this type were easily modifiable, being refit and retrofit between the F5L and the similar F5C-subclass. (ST video game: Starfleet Command)