Jaeger-LeCoultre reference 2450: the Second T.W.O in One

You who follows me here may have read my report on the Jaeger-LeCoultre: 2400 the Two in One. One thing I didn’t point out in that report was the location of the seconds hand.

Like many other watches from this period, brands made several different references for the same case, by using different movement inside…

One example of this is the Memovox E 853 and the E 855 – both share the same case but while the former is without date, the later have the date complication. Calibre 815 vs. Calibre 825.

Jaeger-LeCoultre created the case design for the E 853 and later when the Calibre 825 was launched, included it in the same case and called it E 855. During a period Jaeger-LeCoultre even stamped “853 855” inside the case back, but most case backs read either “853” or “855”.

Jaeger-LeCoultre case back – signed 853 and 855

The second Two in One watch – the reference 2450: here shown in a early 1950’s French market pamphlet

Jaeger-LeCoultre early 1950’s French market pamphlet – reference 2450

Even if the Jaeger-LeCoultre Heritage Gallery have confirmed that the 2450 have the same case system with interchangeable frame, there are two prices stated in the pamphlet – one for steel and one for gold. Possible that the second frame was sold separately?

What differs between the 2400 and the 2450 is the location of the seconds hand. While the 2400 features a sub-seconds, this 2450 have a central seconds application – i.e. different movements inside the T.W.O.

Here is a drawing of the reference 2450, shared by the Jaeger-LeCoultre Heritage Gallery:

Jaeger-LeCoultre drawing – reference 2450

Notice the date: 25th of November 1953. Question that comes to mind is if this is the birth date of the 2450 or simply the date when the reference was documented was created?

The design and size of the 2450 originates from the some period as the Uniplan and Reverso – late 1920’s early 1930’s. Art Deco, 21 x 35 mm.

The only document I have including the 2450 is, based on other watches inside, from the early 1950’s.

Could it be that the 2450 was born as late as 1953? Based on the Uniplan and the Reverso I find it a bit unlikely that the 1953 is the birth year of the 2450 as the central seconds version of the Calibre 11” been around since the early 1930’s.

Even if the case construction did not exist as early as the Reverso, I would be surprised if it was as late as 1953…

Here is an example of the central seconds Reverso from the 24th of November 1934:

Jaeger-LeCoultre 1934 ad – French market Reverso

On the drawing is Calibre 11” stated with a later note of Calibre 437.

The Calibre 437 is based on the same Calibre as inside the reference 2400 – Calibre 424 with the addition of the central seconds.

Jaeger-LeCoultre movement specification – Calibre 437

Further on the drawing is a note of discontinued in 1963 – same year as for the 2400.

There are no production numbers for the 2450, but based on the number of made Calibre 437 one could guess the 2450 production number is even less than the 2400.

Calibre 437 was made in 5.707 pieces during the period 1939 to 1949, only 6.15% of the Calibre 438 production number for the same period… (Calibre 11” with central seconds before 1939 was the Calibre 411).

Here, a movement specification shared by the Jaeger-LeCoultre Heritage Gallery for the Calibre 437: