1 / 4 Replica collection · Railmaster · Anti-magnetic field watch with date
Model reference: 220.10.40.20.06.001
Reference 220.10.40.20.06.001: the Railmaster, a 40 mm field watch with a vertically brushed grey dial, a date at three, printed crossings behind the hands and no rotating bezel, shown in the frames on a black leather strap.
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About this watch
The Railmaster is the field watch in Omega’s Seamaster line, and reference 220.10.40.20.06.001 is the 40 mm steel version with a vertically brushed grey dial and a date at three. Omega’s own data for the reference gives a symmetrical 40 mm case, 12.65 mm of thickness, 47.00 mm from lug to lug and 20 mm between the lugs, a case back with a wave-edged design, a dial with brushed hands and recessed hour-markers filled with vintage-toned luminous material, a transferred beige Railmaster indication, the Co-Axial Master Chronometer calibre 8806 with 55 hours of power reserve, a published 15 bar for water, and resistance to magnetic fields reaching 15,000 gauss.
The four frames on this page are shown as they arrived, and together they cover the dial straight on, the case and strap from an angle, the dial close up and the case back. One thing is worth settling before they are read: the dial is a vertically brushed grey surface, and it reads pale in these frames where the light falls on it, so it can look close to silver in a photograph without being silver. What the frames cannot settle — the movement fitted, the metal of each part, the strap or bracelet supplied, the weight, and the water-resistance state of this particular watch — is asked for in the WhatsApp conversation, and the list at the end of the page sets it out.
It is a field watch wearing a Seamaster case: the Railmaster has no rotating bezel, no tachymeter scale and no crown guards, and the crossing lines printed behind the hands refer to railway-track markings rather than to a timing scale. Take the bezel away and the dial stops being a tool — nothing on it is there to be turned, timed against or aligned with anything.
That is the practical difference between this reference and a Seamaster diver that shares the family name. A diver is organised around a bezel and a depth rating; the Railmaster is organised around a dial that reads at a glance and a case that passes under a cuff, which is why the published 40 mm by 12.65 mm by 47.00 mm shape of the reference matters more to a buyer than the Seamaster badge on it. What those published figures say about the particular watch on offer is a separate question, and the frames on this page are what it should be checked against.
It is a magnetic-field figure rather than a depth figure, and it is the specification this reference was built around. Omega publishes 15,000 gauss for the calibre in place, a number far beyond anything a home or an office produces, so the point of the design is that the ordinary magnetic objects around a wrist are not expected to disturb it.
In use the question is narrower and more useful than the headline figure. The real test for a Railmaster is not only whether the watch keeps time but whether it still keeps time after sitting beside a phone, a speaker or a magnetic bag clasp, and that is a property of the individual movement fitted rather than of the case around it. Timing figures taken before and after that kind of exposure are the evidence that answers it, which is why they sit on the inquiry list at the end of this page.
Because it is a vertically brushed grey surface, and a brushed surface throws light back at whatever stands in front of it. In these frames the dial reads pale where the light lands on it and turns deeper grey as it angles away, which is exactly how a brushed grey panel can look almost colourless in one photograph and plainly grey in the next.
The brush direction is the giveaway worth checking: the strokes run across the dial, they change character at the top and at the bottom under the same light, and the black print sits on top of them. That print does the legibility work here — the brand name and line name above the centre, the two-line Master Chronometer wording beneath them, black numerals at twelve, nine and six, the printed crossings behind the hands, and the date at three.
Those are two separate facts and this page keeps them apart. In the frames the watch is on a black leather strap of the textured, stitched-edge kind; Omega’s catalogue pairs reference 220.10.40.20.06.001 with a fully brushed integrated steel bracelet and a butterfly clasp.
So the strap in the photographs is evidence of what was photographed rather than of what will be handed over. If the bracelet matters to you — and on an anti-magnetic watch a steel bracelet changes both the weight on the wrist and the way the case carries — ask which of the two comes with the piece and how the clasp or buckle looks from both sides. A pair of photographs of the supplied strap or bracelet settles that faster than any description of it.
The published figures are 40 mm across, 12.65 mm thick, 47.00 mm from lug to lug and 20 mm between the lugs, with a total weight of about 149 g for the reference. Diameter alone is the least informative of those numbers, because it says nothing about where the case ends relative to the edge of the wrist.
Compare it with a watch you already wear, measured the same way rather than recalled from a spec sheet: two watches can share a 40 mm diameter and sit quite differently, and 47.00 mm from lug to lug is the figure that decides it, while 12.65 mm of thickness is thin enough for a cuff to pass over. Note as well that the weight above is stated for the reference on its bracelet, so the strap shown in the frames will not weigh the same.
A frame records the outside of a watch in one light and stops there. None of these four shows which movement is fitted, what each part is actually made from, the weight of this watch as it would stand on a scale, or whether it still performs to the published 15 bar for water.
Two of those are questions about state rather than specification, and both belong to the individual watch: water resistance after its own history of use, and magnetic behaviour after its own exposure. The magnetic one is the question to press hardest on a Railmaster, since it is the whole reason the reference exists. Everything the frames cannot answer, and the WhatsApp conversation can, is grouped at the end of the page.
Specification
| Detail | Description |
|---|---|
| Model reference | 220.10.40.20.06.001 |
| Model size | 40 mm |
| Dial | Vertically brushed grey; it reads pale in the frames where the light falls on it |
| Dial print | Brand name and script Railmaster line name above the centre with the two-line Master Chronometer wording beneath; Omega publishes the Railmaster indication as transferred beige |
| Bezel design | None: a fixed polished rim, with no rotating bezel and no tachymeter scale |
| Bezel graduations | None; every scale on this watch is printed on the dial rather than set into a bezel |
| Hour-marker layout | Numerals at twelve, nine and six, with arrow-shaped markers between them |
| Hour markers | Applied arrow-shaped markers with a recessed fill, plus printed numerals at twelve, nine and six |
| Hand arrangement | Three centre hands: hour and minute hands with a pale fill, and a slim centre seconds hand |
| Date display | Aperture at three o’clock showing two digits, with no magnifier over it |
| Subdial layout | None; the dial carries printed crossing lines instead of any subdial or scale |
| Colour combination | Pale brushed grey dial, black print and black numerals, steel hands and markers, and a black strap in the frames |
| Strap shown | Black leather strap with a textured surface and stitched edges, as shown in the frames |
| Strap (reference supply) | Omega catalogues a fully brushed integrated steel bracelet with a butterfly clasp for this reference |
| Movement (reference design) | Co-Axial Master Chronometer calibre 8806 with 55 hours of power reserve, published for the reference |
| Case back | Naiad Lock oriented back with a wave-edged design; an opening in the back is visible in the frames |
| Case thickness | 12.65 mm, published for the reference |
| Lug to lug | 47.00 mm, published for the reference |
| Lug width | 20 mm between the lugs, published for the reference |
| Magnetic-field figure | 15,000 gauss, published for the calibre |
| Water resistance (published) | 15 bar (150 m) for the reference; what the individual watch still tolerates is a separate question |
Questions
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