Almost every top-quality button-down shirt has a tiny fabric loop sewn into the seam where the shoulder blades meet. The loop started way back in the Navy when sailors hung their clothing on hooks to save space. In the 1960s when the collegiate Ivy League look became popular, the Gant company reintroduced the little extra as a “locker loop.” The loop quickly became a status symbol. On some campuses, removing the loop signified that a man was taken and no longer free to date. We can make sure your button-down shirt is crisp and clean, with or without the loop.
From:: Secrets of the loop.