Free data sheet · from the factory catalogue
Six Omega calibres, one set of dimensions.
The 27.90 mm automatic calendar family — 560, 561, 562, 563, 564 and 565 — measures the same, beats the same, and looks the same under a loupe. They are told apart by the number on the bridge and the jewel count. And they are not worth the same money.
This is the same format a paid Movement ID report uses, for one family, free. Every line is graded by how it is known — see the legend at the bottom.
The specifications
| Calibre | Jewels | Built on | Introduced | Marked on |
|---|---|---|---|---|
| 560 | 17 | 550 | 1958 | bridge |
| 561 | 24 | 550 | 1958 | bridge |
| 562 | 24 | 550 | 1958 | bridge |
| 563 | 17 | — | 1966 | bridge |
| 564 | 24 | 563 | 1966 | bridge |
| 565 | 24 | 563 | 1966 | bridge |
All six: diameter 27.90 mm, height 5.00 mm, 19,800 A/h, antimagnetic, Incabloc. Source: Omega GF 620-3 spare-parts catalogue, calibre sections and 1966 supplement folios. Factory sheet.
Two generations, one trap
The first three (560/561/562) are 1958 calibres built on the 550. The second three (563/564/565) arrived in 1966 with one change that matters to a buyer: CORR in the designation — a quick-set date corrector. A 565 sets its date from the crown; a 562 does not. Same size, same beat, different watch.
17 jewels → 24 jewels
Within each generation the jump from 17 to 24 jewels is almost entirely loose jewels replacing bushings in the winding wheels. In the 1966 generation only three prefixed parts differ between a 563 and a 565: the train wheel bridge and the two automatic bridges. Everything else is shared.
What "bulletin" means
561 and 564 are the chronometer-certified versions — bulletin is the observatory certificate. The 561 has exactly one part unique to it: its train wheel bridge. The chronometer premium is paid for adjustment and paperwork, not for different metal.
The 563 is load-bearing
It supplies the entire date mechanism to the 613 and the whole base of the 752. If you are hunting parts for either, the 563 section is where they live.
What to check before you buy
| Check | Why | How |
|---|---|---|
| Read the bridge, not the listing | Sellers copy the calibre from a previous listing more often than from the movement. | The number is stamped on the train wheel bridge. Photograph it. |
| Count what you can't count | 17 vs 24 jewels is invisible by eye and worth real money. | Trust the printed jewel count on the plate; check it agrees with the calibre number. |
| Does the date quick-set? | If it does, it isn't a 560/561/562. | Pull the crown to the first click and turn. CORR calibres jump the date. |
| Does the case belong to it? | A 565 in a case built for a 564 is a marriage. | Case reference inside the back, checked against the 2012 case sheets. |
That was one family, for free. The report does it for your watch. Six photographs and the weight. I identify the calibre, check whether the case was built for it, date the serial, judge the dial, grade the wear, and give you three values — as a watch, as parts, as metal — with every fact graded and cited. In writing, in a day, US$75. You pay nothing until I've confirmed the photos can support an answer.
How to read the grades. Factory sheet: printed in an Omega catalogue or technical guide I hold, volume cited. Stamping: read from the metal. Community: established among collectors, not traceable to a factory page. Unverified: my reading — treat as a lead.
Specifications are transcribed from printed catalogues and may contain transcription errors; corrections are welcome and published. Watch Breaker is an independent identification specialist and parts dealer and is not affiliated with, endorsed by or connected to Omega SA or the Swatch Group. Omega is a trademark of Omega SA. Terms.