The fly is the front opening at the top of jeans where you’ll find either buttons or a zipper. On jeans, the top button is also uncovered.
Why the heck did you put a zipper in your jeans? It’s like peeing into the jaws of an alligator.”
So go the famous words of an anonymous customer who wrote to Levi’s when they introduced zippers on their flies in the 1950s.
Today, we take the zipper for granted and their ease of use means they are appearing more and more often on today’s high street jeans. However, for many denim purists, however, it’s buttons on the fly or nothing at all.
Before the invention of the zipper in 1913 by Swedish-American Gideon Sundbäck, all pants were fastened with buttons (or lace-ups, if you go really far back), which were considered the norm for jeans and overalls.
Lee was the first jeans maker to put a zipper in jeans in the 1920s.
With the button fly being considered somewhat lacking in modesty, manufacturers favoured the zipper, which was easier to do up and offered a sleeker, flatter profile along the crotch.
This is an aspect of jeans construction that has carried through to the modern day, with the majority of jeans made for women sporting a zipper over a button fly. Furthermore, with today’s fashion for tighter, and skinnier fitting jeans, often a button fly adds unnecessary bulk to the crotch area and can stretch and distort the profile of the garment.
For denimheads though, the button fly is usually the fastening method of choice, both for their place in denim history and the interesting fades they create on the fly over time.