Case size: 39 mm
Material: steel/gold
Movement: automatic, caliber 2121
Year: circa 1979
Crystal: sapphire crystal
Bracelet: integrated original bracelet, folding clasp
Reference number: 5402SA
Movement number: 173'648
Case number: B18847 / 109
Accompanied by: certificate, box
Service papers from 2023 are included.
The watch is in overall well-preserved vintage condition, with some age-related wear on the case and bracelet. Serviced in 2023, and the movement is in good condition. The bracelet has minor stretch. The "Swiss Made" at 6 o’clock suggests the dial is either part of a later production batch or has been refreshed after the mid-1980s. The hands have been replaced.
The Audemars Piguet Royal Oak ref. 5402 is the original Royal Oak reference, introduced in 1972, pioneering the concept of a luxury sports watch with an integrated bracelet and an ultra-thin automatic movement. Designed by Gérald Genta, the watch was initially produced exclusively in stainless steel, setting a new standard for high-end watchmaking. Due to its 39mm case diameter, which was considered large for its time, it became known as the "Jumbo".
In 1977, Audemars Piguet introduced the 5402SA, a refined two-tone version combining stainless steel and 18k yellow gold. This model remained significantly rarer than its steel counterpart, with only 876 units sold, numbered from 1 to 951. With serial number 109, this example is an early production piece within the 5402SA series.
This watch is powered by the Caliber 2121, an ultra-thin automatic movement based on the Jaeger-LeCoultre 920. Measuring just 3.05mm in height, it remains one of the thinnest full-rotor automatic movements ever produced.
The dial features the petite tapisserie pattern, a defining characteristic of the Royal Oaks. The "Swiss Made" marking at 6 o’clock suggests the dial was either part of a later production batch or refreshed after the mid-1980s.
Originally sold on March 30, 1979, this watch is accompanied by its original box and guarantee papers, which are rarely preserved with early Royal Oaks. It has also undergone a full service in 2023. As the first Royal Oak reference and a rare two-tone variant, it holds an important place in Audemars Piguet’s history.