This is our series: Same or Different, Where We Multiply with -1.

Steel sportwatch genealogy & chronometer chronology. The Jaeger LeCoultre ref24001 Master Mariner was introduced to the market in 1973 -- one year after the most important draft of Gerald Genta was presented by Audemars Piguet: the Royal Oak, and four years before Gentas most popular Patek was released: the Nautilus.

There are so many similarities between the JLC and both siblings that one is left wondering why the characteristic JLC is completely overlooked:

• The introduction to the market as expensive sport-chic steel watch.
• Diver Helmet, Master Mariner, Porthole. The nautical theme was Gentas most beloved reference: courage, adventure, freedom, strength and resilience -- in one watch by just a name and a few adoptions of some nautical elements. Genius.
• The robust integrated bracelet (made by Henry & Fils Cie, Geneva, a competitor at eye level with Gay Freres) that wears comfortable and makes a unity with the watch and a sporty statement.
• The typical Genta design-language: "Round and Angled" (RaA). A octagonal case with a elliptical bezel and dial, that gives the watch so many similarities to the Royal Oak, the Nautilus and the Yacht Club II -- and to almost any other later arriving design hit from Genta.
• The striped two tone dial: something that we find in the Nautilus Patek ref3700 as one of its most characteristic attributes.
• While AP Royal Oak & Patek Nautilus were given a Ebauche by Jaeger LeCoultre, the JLC cal920 to name it AP cal2120 or Patek cal28-255 and to put it in their flagships, Jaeger developed its own sophisticated automatic movement for the Master Mariner -- the in many aspects superior cal906.

The chronometer grade automatic movement JLC cal906 was not as thin as the JLC cal920 (AP2120 or VC1120 or Patek28-255) but it was antimagnetic, had a hacking seconds feature and was more precise than the more widely used workhorse. And interestingly it was also used by Vacheron Constantin in their Chronometre Royal reference 42001 (!sic, not 24001) that appeared in 1975 and looks like the JLC ref24001 edgewise, rotated 90 degrees. Even the date window moved from 3 to 6 o'clock and the hands are the same...

So, it seems like the JLC ref24001 is the template and model for the Patek Nautilus ref3700 in many aspects and the Vacheron Chronometre Royal ref42001 in total. Even more, it seems to be one of the most important elements in the series of steel sportswatches that connects both behemoths: Audemars' Diver Helmet & Pateks Porthole. The JLC ref24001 Master Mariner -- A horological archaeopteryx or even better, to stay maritime: a horological lungfish or coelacanth.

Addendum: Just to make sure the point is clear: In case the above mentioned aspects are true, then we stand in front of a completely revised chronology and change in importance of the pinnacle of Swiss watch-manufacturers, the steel sportswatches. The two inserted watches, JLC MasterMariner & VC Chronometre Royal are much more important than what the market currently thinks: not only they were equipped with a more powerful, innovative and expensive movement while the competitors Audemars & Patek were given the much cheaper JLC cal920 Ebauche for their flagships, but also they (JLC & VC) seem to be the template for the Patek Nautilus, that becomes now just a small evolutionary step from the predecessor VC Chronometre Royal (that itself is just the JLC MasterMariner turned by 90 degrees) and is far from the revolutionary standalone design by Genta, it is so far treated as.

See the other parts in this series here: #SameOrDifferent