As we all know zippers are obsolete in the 24c
Beverly uses her zipper in "Naked Now".
A simple mistake. It was Gene's "vision" that by Trek's time zippers were obsolete and no longer used. In NN it's either a pure mistake simply from it being early in the series or what Beverly grabs for is simply a zipper-like device that's not an actual zipper.
Likely, again, something we're "not supposed to see" and is supposed to be an invisible nanoseam.