You may have noticed that a lot of backpacks have a little leather square sewn right on the front. Just like the tiny pocket in your jeans or the hole in a spaghetti spoon, the design, which is found commonly on Herschel bags, is about more than just style.

The little diamonds—called lash tabs or pig snouts—have two parallel slits cut out of the center. This lets you weave a cord or string through and tie various items—shoes, a water bottle, a flashlight—to your bag. The strong little square is built to hold your larger items while hiking or traveling, but it can also be used for smaller objects like earbuds or name tags.

[h/t Lifehacker]