<P> Cadet ranks are rarely ever seen, with the exception of the various visits from Wesley Crusher to the Enterprise in TNG . As it appears in those instances, it can be surmised that the insignia of a Cadet consists of 1, 2, 3, or 4 copper and black bars, similar to those of a modern Lieutenant in the United States Army . It can also be surmised that if a cadet has 1 bar, he has 1 year at the academy . 2 for 2 years, and so on . </P> <P> Enlisted ranks are seen even less; their insignia are unclear . </P> <P> Deep Space Nine introduced a new style of uniform that appeared to run in parallel to the one seen on TNG . The new uniform comprised a single two - piece open - necked jumpsuit with the colored and black areas of the TNG uniform reversed (black torso and colored shoulders) and the science division is now blue - green with the upper - part being a removable jacket along with a visible zipper . A grayish - indigo mock turtleneck undershirt was added, to which rank pips are affixed . The characters of Major Kira and Odo did not wear Starfleet uniforms, as they were part of the Bajoran forces . Throughout the run of DS9, ship - based Starfleet personnel continue to wear the older uniform design . Sisko also wore the TNG uniform on certain formal occasions, during his first arrival at DS9 (in the series pilot episode, "Emissary"), and when he was temporarily given the duties of "Head of Security" for Starfleet Headquarters on Earth (in the Season 4 episode, "Paradise Lost"). Admirals also retained the TNG style . A uniform similar to that appearing in the DS9 series can be seen in the TNG Season 3 episode "Allegiance", worn by the alien masquerading as a Starfleet cadet . The uniforms were first used in the premiere episode, "Emissary" and would continued to be used up to the Season 5 episode, "The Ascent". </P> <P> Following the release of Star Trek: First Contact, the new gray movie uniform design also appeared in DS9's fifth season and for the remainder of the series . However, the old DS9 uniform appears four more times following the introduction of the movie gray uniform design in the Season 5 episodes, "In Purgatory's Shadow" and "By Inferno's Light" as well as the Season 7 episode, "Field of Fire" in a photograph and in the flashback scenes of the series finale, "What You Leave Behind". </P>

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