Apple’s new 16-inch MacBook Pro not only has a bigger screen, but it returns to a scissor switch keyboard, has louder speakers, a better mic, and a... lid angle sensor?

MacRumors found the mention of the new sensor in a service document that was sent to Apple Authorized Service Providers. It shared the info with iFixit, which found the small sensor inside the computer and also noticed that the MacBook Pro’s hinge has a magnet inside it with an arrow that indicates the hinge’s polarity.

But that’s as much as we concretely know about the lid angle sensor. Based entirely on the name, it seems likely that the sensor can track the exact angle of the lid in some way. iFixit also speculated that the sensor helps keep a history of how much the display has been adjusted, perhaps to help Apple diagnose any potential “Flexgate”-like backlight issues that could appear on the laptops in the future.

Without more information from Apple, it’s hard to know exactly what the sensor might be for. MacRumors did see in the service document that both the computer’s display and lid angle sensor need to be calibrated before a repair is considered to be complete, so Apple seems to want to make sure the sensor is handled properly.