Analysis, part 4 - Seam Lines and Zipper

Like the DS9/NEM "captain jacket" and "captain vest" of the era, the duty trousers were also of 8-panel construction:

Jadzia

The seam lines of the duty trousers ideally segued smoothly with those of the jacket body and/or vest body:

Bashir

Ezri

On Captain Janeway, the duty trousers' seam lines were aligned with those of her "female her undershirt":

We can safely assume that the same was true for B'Elanna during the one episode she wore the duty trousers with the "female hero undershirt," and, perhaps, by extension, that this was also the standard for the men's duty trousers and "hero T-shirts."

VOY, 6x22 "Muse"

VOY, 5x9 "Thirty Days"

We can't say for sure, though, since we haven't actually verified this with our own eyes ... it'd just make sense, 'tis all ...

The men's duty trousers closed up the front with an invisible zipper. 

However, for whatever reason, the costuming department didn't bother trying to hide the zipper pull as they had with the other Starfleet uniform garments of the era (such as the duty jumpsuits). 

We never actually saw the zipper pull on-screen; the combination of it being so tiny, matching the color of the pants, usually being in the lower frame if at all, and not being located in a place where most viewers' eyes would be focusing is probably why, and also why nobody bothered hiding them. 

However, the duty trousers' zipper pulls have often been plainly visible in auction photos:

The Sisko

Worf

The same was true on Voyager:

Tom Paris

Tuvok

(We'll take a look at the ladies' closure later.) 

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