I mean, the company has never really said how their systems worked. It's basically left the users/scanned with the impression that it's magic. It seems to me that it's basically some of 3D metal detection paired with cameras. It would be cool to understand how they make it work, but I guess it's a trade secret. They haven't readily put up numbers about false positive rates, and even less data about false negatives. I get the impression that this relies heavily on placebo effect - "they have scanners so I better not try to take my weapon in".