Royal Oak 26240ST: The 50th Anniversary Chronograph
The Audemars Piguet Royal Oak chronograph reference 26240ST continues the collection’s familiar octagonal bezel and integrated bracelet. The 50th Anniversary version adds a specific commemorative detail that matters when identifying an example: its dedicated winding rotor.
The Anniversary Details
Audemars Piguet’s reference page identifies the blue dial 26240ST.OO.1320ST.01 as a 41 mm steel anniversary chronograph. It describes the Grande Tapisserie dial in Bleu Nuit, Nuage 50 and a dedicated 50 years oscillating weight visible through the caseback.
The broader 26240ST reference family should not be treated as proof that every example is the anniversary version. Confirm the complete reference, caseback details and documents for the individual watch.
Chronograph and Everyday Display
The three subdials and date window sit within the patterned blue dial. The 26240ST family uses the automatic calibre 4401, with a flyback chronograph. AP’s 4401 specifications describe a 70 hour power reserve. A flyback lets the chronograph restart an elapsed time measurement in one operation; ask for a demonstration using the watch’s manual.
Look Closely at the Bracelet and Finish
The mix of brushed and polished surfaces is a major part of the Royal Oak design. Examine those edges, the bracelet’s condition and the number of included links. A diameter figure alone does not tell you how the integrated bracelet will fit your wrist.
These are archived store photographs. Before buying a current example, review its condition, service history, chronograph operation and documentation, and confirm availability and terms directly.
Contact Diamonds by Raymond Lee to discuss your piece or arrange a visit to our Boca Raton showroom.