Editorial
The Millenary 4101 is AP's most structurally unconventional watch: a 47mm rose gold oval housing a flying tourbillon at 9 o'clock and a fully skeletonized movement that reads as kinetic sculpture rather than dial. Collectors come to it because they want AP's horological credibility without the Royal Oak's ubiquity, and they leave with something genuinely rare in the current market.
AP introduced the current Millenary 4101 reference (15350OR.OO.D093CR.01) in 2011 as a rose gold only proposition, pairing the in-house Calibre 4101 manual-wind flying tourbillon with the oval case that has defined the Millenary line since the 1990s. The 4101 caliber beats at 21,600 vph and delivers a 72-hour power reserve, with the tourbillon cage positioned off-axis at 9 rather than the conventional 6, which reinforces the deliberately asymmetric composition. AP offered limited color and strap variations over the run but never rehoused the 4101 in white gold or platinum, keeping rose gold the only metal option for this configuration.
The reference was discontinued around 2022 when AP rationalized the Millenary line, which is starting to register in secondary-market pricing as supply tightens.
The skeleton bridges and tourbillon cage are fragile relative to a standard movement and do not tolerate amateur servicing or shock; always request service records and verify the work was done by AP or a certified independant with flying tourbillon experience. The crown at 9 o'clock shares the case band with the tourbillon side, so worn or damaged crowns can indicate the watch was used hard or stored carelessly against hard surfaces. Strap condition matters more than it might on a bracelet watch: the crocodile strap on this reference is curved and fitted to the oval lugs, and AP aftermarket straps are expensive.
Inspect the sapphire caseback carefully for scratches, since the movement display is a core part of the value proposition and a hazy caseback signals past neglect. Finally, confirm originality of the crown and crown tube, which are sometimes swapped during unauthorized work.
