In a blog titled Those forgotten pant parts, Levi Strauss & Co. say this tiny pocket was actually for holding a pocket watch!
"The first blue jeans had four pockets—only one in the back and, in the front, two plus the small watch pocket," said the article.
"Originally included as protection for pocket watches, thus the name, this extra pouch has served many functions, evident in its many titles: frontier pocket, condom pocket, coin pocket, match pocket and ticket pocket, to name a few."
The article also clears up many other design elements that might not make much sense. For example, why do your jeans have tiny buttons on them?
While pocket watches aren't standard anymore, with many people choosing to keep time with their phones, the tiny pocket still exists on many jeans today.
Speaking to Insider, Tracey Panek, the in-house historian at Levi Strauss & Co., says it's to maintain the classic Levi design.
"The watch pocket was an original element of our blue jeans, like the rivets on our pockets, button fly, arched back pocket stitching and leather patch."
"To preserve the integrity of the early design, Levi Strauss & Co. maintains the watch pocket."
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