ETA 251.233 COSC Thermo Compensated Quartz Chronograph Watch Movement

ETA Caliber 251.233 COSC

ETA 251.233 COSC Thermo Compensated Quartz Chronograph Watch Movement

Manufacturer ETA
Caliber Number 251.233 COSC
Type Quartz, chronograph
Diameter Unknown (please comment below)
Battery Cell Number 394
Hacking? Yes
Stem Unknown (please comment below)
Hand Sizes Unknown (please comment below)
Jewels 27
Functions Hours, minutes, 1/10 seconds, small seconds, central chronograph seconds, central chronograph 60 minutes, 12 hours, date
Country of Manufacture Switzerland
Known Models
Invicta 12959, Christopher Ward C7 Racing Red

This movement appears to be discontinued. It is not found on the ETA website, nor can replacements be easily found online. Please comment below and share everything you know about this movement.

From Invicta:

In this circumstance, the Thermo Compensated Movement is being utilized in these watches. The thermo compensated movement is made by ETA 251.233 and is comprised of 27 jewels. This fact differs from most quartz movements which generally do not have any jewels in the movement. The ETA 251.233 in entirely Swiss Made. These are the most accurate certified quartz caliber movements currently available; the movement maintains a -15 seconds per year. Due to their exceptional accuracy, thermo compensated quartz watches take accuracy in performance to another level in timekeeping.

From Christopher Ward:

To gain chronometer status, watchmakers submit their Swiss movements to COSC, an independent, non-profit making watch accuracy verification organisation based in Geneva, to be tested against the international standards of ISO and DIN.

Certification follows exhaustive testing. In achieving the coveted status of Certified Chronometer, a movement must not only be made from the highest quality components, but also be the object of special care on part of the finest horologists and technicians as it is painstakingly assembled.

Only movements which meet the precision criteria are granted an official certificate. Each uncased movement is individually tested for fifteen days, in five positions, at three different temperatures.

Movements are fitted with a second hand for tests and measurements are made daily with the aid of cameras. Based on all of these measurements, seven eliminatory criteria are calculated, each of which must be met.

The exacting and rigorous nature of the COSC certification process means that the achievement of Certified Chronometer status is extremely rare. In fact, of all the watches produced in Switzerland each year, just 3% bear the coveted COSC ‘bulletinde marche’ or certificate of watch performance.Which is why, when you read the words ’Certified Chronometer’ on a Swiss watch you can be sure that the movement behind the elegant dial is a rare example of fine Swiss watchmaking which is accurate, precise… and extremely rare.

ETA 251.233 Battery

Is the ETA Caliber 251.233 COSC any good? Share your opinions, experiences and watches below... Remember to keep comments respectful and follow our community guidelines.

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Alojamiento web

For new collectors and those interested but unfamiliar with the vast number of movements available in the luxury watch market, the ETA movements prove to be a good place to start.


Although I only have 1 quartz watch in my collection it does have the ETA Caliber 251.233 COSC movement and I’ve had this for 3 years it only loses 3 seconds a year/


I own one watch that has the ETA 251.233 COSC movement. It runs about -4 seconds after six months. Overall I am pleased with this movement. The center chronograph minutes hand makes this movement stand out from other chronograph movements.

Jack Wright
Jack Wright

Is it in an Invicta JT LE-12589.
That’s the watch I have with the same movement. 1 second a year on or off the wrist.