Also making the cut for this "impossible to counterfeit" timepiece—their boast, not ours—are layers of invisible UV marking, laser perforations of the watch's internal parts, high-security inks, and special secret measures that are used to secure passports and currencies.
Some of the 400 models even have tiny text on the dials that is readable only with a magnifying glass. And, like the watch, even the text is full of itself, as it reproduces portions of some letters sent between 19th-century family members of the watchmaker, Jaques-Barthélémy Vacheron and François Constantin.