Continuity: Klingons measure distance in kilometers in this episode. However, in all other Trek shows and movies, they measure in kellicams. [This was apparently during a misguided attempt by the Empire to adopt the decimal system (for Galactic consistency), even though the change was wildy unpopular with the public and military alike. While some ships, like in this episode, gave it a good try, the change was short-lived and eventually abandoned. However, until this claim can be backed up by a reference within Star Trek canon, it stands as a mistake.]