We've been getting a number of questions from readers about a mysterious "patch" on the edge of all of the iPhone 12 models introduced today. The patch is unlabeled on Apple's specs page, but The Verge has confirmed that it is a window for the mmWave 5G antenna.
mmWave 5G support is only included on U.S. models of the iPhone 12 lineup, and thus the window is only present on those devices, as seen in images shared on Apple's pages for various countries.
Side-by-side comparison showing U.S. phones with the antenna window and international phones without (via Apple and The Verge)
The mystery patch was first seen in leaked schematics dating back many months, and was initially speculated to potentially be a Smart Connector or docking site for a small Apple Pencil, given its similar appearance to the magnetic Apple Pencil attachment site on iPad Pro models. That speculation was, however, quickly dispelled as new rumors indicated it was for a 5G antenna.
Article Link: Mystery Patch on Edge of iPhone 12 is a mmWave 5G Antenna Exclusive to U.S. Models