Oh ok, sorry about that. Are you talking about the USB port? I do not see an SD card slot on the body but there is a USB port which I don't think allows for customers to utilize for anything. It might be for factory or technical support use but I'm not sure.
As you suspected, amctr, this likely stores flight data which can be accessed/downloaded to a computer via the Micro USB port on the X-Star body. Not sure I'd ever bother trying to download this information but it could be useful to Autel, the FAA, or the curious