5402ST B-Series
Royal Oak Jumbo 5402 — 5402ST B-Series
1975–c. 1977
Small numbers B1000–B2000; numbers below 1,000 were left unused, probably so only the A series had them. The first, B1044, left Le Brassus on 21 March 1975 for Guam. Not to be confused with the internal “big case number” that also starts with B from 1975.
845 sold: 228 (1975), 569 (1976), 23 (1977), then a few to 1993. Dated example: B1303 (mid-1970s).
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Identifying details
Variants of 5402
Reference overview →| Variant | Production |
|---|---|
| 5402ST A-Series | 1972–c. 1976 |
| 5402ST A-Series · Steel bezel screws (earliest examples) | c. 1972 |
| 5402ST without small number (Intermediate series) | 1974–c. 1976 |
| 5402ST B-SeriesCurrent | 1975–c. 1977 |
Case & movement
- Reference
- 5402
- Production
- 1975–c. 1977
- Case serials
- c. 1,000–2,000
- Case material
- Stainless steel
- Case diameter
- 39 mm
- Water resistance
- 100 m
- Crystal
- Sapphire
- Movement
- Automatic
More specifications (2)
- Date
Movement
Audemars Piguet 2121
Date version of the 2120, introduced in October 1970 in model 5381 and chosen for the first Royal Oak in 1972; at the time the thinnest automatic with central rotor and date. Ébauche from LeCoultre & Cie until about 2002, then made by AP; replaced by the 7121 in 2022.
Automatic · Introduced 1970 · 19,800 vph · 36 jewels · 40 h reserve · Ø 28 mm · 3.05 mm thick