These informations were mostly gathered through my own experience, from watches I actually had in hands. They reflect what I observed and are not the holy truth. Page updated August 26th 2026 : 8418 model added.
Text & Pictures : D. Broglin – Watch & Vintage
This is an attempt to list all Ultra-Chron models and their variations, from 1967 to 1974. Work in progress of course !
1st generation, calibre 43x (1967-1970)
7827
monobloc case
1967
7831
1970
7851
monobloc case
1970
7951
screw back
1968-1969
7952
screw back
7970
screw back
1967-1969
7991
screw back
1967-1969
8019
8022
8071
8309
34.5 x 40.5 mm
monobloc
1969-1970
8351
Chronometer
8352
Chronometer
8353
screw back
Chronometer
1969-1970
8355
Chronometer
8356
Chronometer
8430
plain 18 k gold
8442
monobloc
39.7 x 38.3 mm
8455
monobloc
38.1 x 39.2 mm
8472
2nd generation, calibre 66xx (1971-1974)
2330
screw back
8301
37.2 x 42.0 mm
screw back
8353
8383
8418
34,2 x 38 mm
Original mesh bracelet
I have a gold Longines Ultra Chron and would be happy to share a photo. How can I tell which model it is?
Hi Charlie,
The model reference is engraved inside the case or, if the case back is screwed, on the inner face of it. You can send me a picture to [email protected] if you want and we’ll try to find out more information about it.
David