Miyota caliber OS2O

Miyota Caliber 0S20

Miyota caliber OS2O 0s20
Example of a Miyota 0S20 in a Philip Stein Extreme Chronograph Watch
ManufacturerMiyota (Citizen)
Caliber Number0S20 (sometimes typed as OS20)
TypeQuartz
Replaces CaliberUnknown, please add in the comments below
Diameter13.50”’ (30.80mm)
Height5.1mm
Battery Cell NumberSR927W (395/399)
Battery LifeApproximately 5 years
Frequency32,768Hz
Quartz TypeTuning fork type quartz crystal
Stem065-441 (tap 10)
Hand Sizes1.20/.70/.17 (small hands also .26)
Jewels0
FunctionsHours, minutes, central chronograph seconds, 60 minute counter, 24 hour hand, date
Country of ManufactureJapan
Known Models
Bulova chronograph, Philip Stein Extreme Chronograph, TW Steel A1GP Chrono (Too many to list, add yours to the comments below…)

The Miyota caliber 0S20 is a quartz chronograph watch movement. You might also see other listings incorrectly refer to this movement at OS2O, but is should be zero-S-2-zero not O.

Accuracy:

Miyota claims the accuracy of this movement to be +/-20 seconds/month.

Recalibrating the chronograph hand to zero:

It is common for a quartz chronograph hand to be misaligned after a battery change. If your central chronograph second hand (or chronograph minute hand) is not resetting to 12:00 or “zero” position, you can try the following steps:

  1. Pull the crown to position 2
  2. Press button A (top button) to advance the chronograph hand forward until it is lined up with 12:00. If you long-press A, the hand will move forward faster.
  3. Push button B (bottom button) to reset the 60 minute chronograph hand (subdial located at 9:00).
  4. Push the crown back to position 0

Note: if you push the crown back in to position 0 while the chronograph hand is still advancing forward, then it will stop the chronograph hand and recognize it as zero position. In this case, you will have to start over again.

Miyota 0s20 Chronograph Reset

Replacement prices:

The average replacement price at the time of this post was from $26.95 – $36.95. Try here.

Macro Gallery:

Examples of watches with Miyota caliber 0S20

Additional Resources:

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Arthur
Arthur
4 years ago

What movement is used in the majority of Bulova Marine Star watches?
Unable to find answer anywhere on the internet.

Arthur
Arthur
4 years ago

Is it the Miyota OS20 or the Miyota OS10 that is used in Invictas Corduba
With 2 marvelled registers chronograph? One register atop the other in
Center of dial?

Arthur
Arthur
4 years ago

Auto correct. Marveled registered should have read Barreled Registers in
Center of the dial.

Michael
Michael
3 years ago

Is there an AC pad? Wondering if it is the (-) marking.

Aaron
Aaron
3 years ago

Is there any way to modify the OS20 movement do that it keeps time half as fast as normal?

So that it would work with a 24hr watch.

Jim
Jim
3 years ago
Reply to  Aaron

That is an interesting question Aaron. Can you explain more?

Martin
Martin
2 years ago
Reply to  Jim

Hello Aaron,

yes, this can be accomplished by a hardware modification:
simply replace the 32768 Hz crystal with a 16384 Hz crystal
and the watch will run at half the original speed.

The downside of this modification is that the chrono speed will of course also be halved.

Regards
Martin

Herbert Gomes
Herbert Gomes
3 years ago

I would like to get the pointers to the 0S20 model. How do I do?

Jose Enrique Prades
Jose Enrique Prades
3 years ago

tengo un rolex que por dentro es igual que este de la imagen ,me estan diciendo que no es rolex autentico ,no me lo creo,si fuera imitacion no llevaria esta mecanica

Edwin
Edwin
1 year ago

Tu Rolex es falso amigo. Los relojes Rolex son suizos, fabrica sus propios calibres y ademas casi todos son automaticos a escepcion del Rolex Oyster Quartz

Wilson
Wilson
3 years ago

Para que sirven las indicaciones A1 A2 A3 A4 y los demas simbolos escritos en la parte de atras de los miyota os 20 demas calibres.

Wilson
Wilson
3 years ago

Para que sirven las indicaciones A1 A2 A3 A4 y los simbolos en la parte de atras de las maquinas miyota os20 y en otros calibres.

Tony
Tony
2 years ago

Where can I get a new face dial for the Miyota OS20 plus new Sub Dial Hands, what is the size of the Sub Dial hands
Many thanks & kind regards
Tony
Tony Arnold
arny@helios-electronics.com

Tony
Tony
2 years ago

Many thanks have ordered hands on Ebay
Kind Regards
Tony
Tony Arnold

Tyo
Tyo
2 years ago

Hi.
I have jorg gray 6500-11 with miyota os20 machine, i have problem to reset chronograph minutes hand on 60 position, when set crown at 2nd position then i pushing B button, the chronograph minutes hand back to 15 position, in anotherhand chronograph second hand back to 12 or zero position ..how to reset chronograph minutes hand?

Thank you

Martin
Martin
2 years ago
Reply to  Caliber Corner

Hello Tyo,
I have answered your question in the comments to the Miyota Caliber 0S10 on this site
Regards
Martin

Luis Santos
Luis Santos
2 years ago
Reply to  Caliber Corner

The instructions are about the seconds chronograph hand only. There is no such way to easily reset the minutes chronograph hand.

Ray
Ray
2 years ago
Luis Santos
Luis Santos
2 years ago

The german watch Dugena, model “Monza WR100”, also uses Miyota 0S20 caliber. It’s also marked on the steel back cover.

David Z
David Z
1 year ago

This movement was used in the older Invicta Speedway 9211. the current movement is the Hattori VD53B-14, with the chronograph seconds at 6:00

Stephen Borchert
Stephen Borchert
1 year ago

Reactor Photon 79015 Chronograph.

MdeBruns
MdeBruns
1 year ago

Is it possible this mechanism Miyota OS20 inside a Tag Heur original?

Luis Santos
Luis Santos
1 year ago
Reply to  MdeBruns

Everything is possible. And this is a really reliable and good quartz movement.

MdeBruns
MdeBruns
1 year ago
Reply to  Luis Santos

Luis, thank you for your reply. What i’m trying to know is : A Tag Heuer whatch, original, have this mechanism, or is a replica ?

Luis Santos
Luis Santos
1 year ago
Reply to  MdeBruns

I’m not sure, but if could bet would be a NO. I don’t think, despite its quality, that a original Tag Heuer would use o Miyota caliber.

MdeBruns
MdeBruns
1 year ago
Reply to  Luis Santos

Tks, Luis !!

Luis Santos
Luis Santos
1 year ago

How can I adjust the minutes (not the seconds) chronograph hand?

Alin
Alin
1 year ago
Reply to  Luis Santos

hey Luis, did you find a solution how to calibrate minutes hand from the chrono function?

WISeman
WISeman
11 months ago
Reply to  Alin

You cannot do that.

Damian M
Damian M
1 year ago

my OS20 resets the chrono seconds hand back in time every single time… when i calibrate the hand to top 12… run the chrono a few seconds and reset it it will be somewhere between 9-10… if i do it again it will be somewhere between 6-7… again it will be between 4-5… and over and over and over…. will never reset itself back to the 12 oclock position i calibrated it tooo/… any thoughts???… Read more »

Luis Santos
Luis Santos
1 year ago
Reply to  Damian M

This malfunction can occur due to low battery. Try to replace it.

Fernando
Fernando
9 months ago

This movement is used in the Nautica Chronograph 100m

jeicol
jeicol
5 months ago

how can I return the minute pointer of the chrono back to zero position?? philipp plein Spitfire watch uses Miyota 0520 too

Loh SK
Loh SK
1 month ago
Reply to  Caliber Corner

My expereience with OS20 is a loose fit of the minute to the pin on the movement. Because the minute hand have to fly back to zero position, a loose fit will result in the minute hand returning to different positions . Look for a tighter fit minute hand

trackback
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3 months ago

[…] Miyota 0S20 quartz runs at the heart of the Halyard Sport. Miyota is known for making high-value […]

Belén
Belén
2 months ago

Hola de q parte son? Quiero comprar está makina soy de argentina

Alberto Carballo
Alberto Carballo
1 month ago

Does anyone know how to dismount the stem? Where do I have to push for the stem go out? Thanks

Sam
Sam
6 hours ago

I have this movement in my Nastro Azzurro, se pictures.

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