since i've seen it asked what purpose sleeve garters serve:
Sleeve garters are just so you can keep your cuffs right where you want them, typically used professionally by people like bartenders, who are wearing dress shirts to do manual labor and don't want their cuffs brushing through spills when they are wiping down the bar etc... but also useful for keeping cuffs exactly the right length for your suit without having to tailor all your shirts, or, if you have several suit coats with slightly different length sleeves, you can always have your dress shirt's cuffs showing that perfect half inch below the suit sleeve or whatever the fashion is for the time
right now it's about 1/2 an inch, but that's the sort of thing, like tie length, that can change a little with fashion trends -- but basically, you never want your shirt cuffs to be doing this
Because that looks SO sloppy, right? Looks like you're wearing your father's shirt under your little brother's jacket
BUT! you do want the cuffs showing, like this
because it makes the suit sleeve look precise and on purpose, or you might push it and show even more if you are wearing nice cuff links
because this clearly still looks purposeful and precise, and shows off your jewelry.
often, fashion dictates taking any opportunity to show your layers -- for example in medieval europe it was fashionable to literally slash expensive outer garments so you could ALSO see some of the expensive clothing underneath, which is how before long you get "slashed" sleeve patterns like this becoming popular among the wealthy
(notice the roughly half inch of sleeve cuff showing at the bottom here as well)
So a sleeve garter allows you to keep your sleeve cuffs positioned exactly where you want them, for either fashion or activity
