Like a coat's inside pockets, that extra tiny pocket on jeans, and those weird zippers that have two zips, there are some fashion details you just take for granted. They're just there whether you use them or not. But that diamond-shaped patch on your backpack? Prepare to get schooled. Whether you're sporting a throwback Herschel bag or you had one on your trusty JanSport back in middle school, many backpacks feature the seemingly superfluous add-on. But Marie Claire did a deep dive and found out that the humble patch actually has very utilitarian roots. The fashion mag found out that these leather (and sometimes plastic) patches are actually called "lash tabs" or "pig snouts." While we're keen on using animal noses to describe fashion items, we're not sure that particular term will catch on. Lash tabs, on the other hand, may be familiar to outdoorsy people or avid mountaineers. They were originally used to attach extra gear. Using cords or straps, you could carry a canteen on your lash tab. You could hang a flashlight from it. Marie Claire even suggests using a lash tab/pig snout if you're short on luggage space or as a clever way to avoid overweight baggage fees. By threading the laces of your sneakers (or any laced shoe) through the lash tab and hanging them off your bag, you can free up some space and weight in your checked luggage or carry-on. Now if someone wants to explain why nobody ever designed an attachable lunch bag for our middle school days, we're all ears.