OMEGA · De Ville Prestige
OMEGA De Ville Prestige 434.10.40.20.10.001: specs and checks
The same calibre as the Diver 300M, in a case rated to thirty metres instead of three hundred. A useful reminder that depth lives in the case, not the movement.
Reference 434.10.40.20.10.001 · specifications read from the manufacturer on 2026-09-23 · listed as current
Specifications
As published by OMEGA. A field the manufacturer does not state is left out rather than filled in.
- Case
- Steel, 40 mm
- Diameter
- 40 mm
- Thickness
- 9.93 mm
- Lug width
- 19 mm
- Lug to lug
- 46.26 mm
- Water resistance
- 3 bar (30 metres / 100 feet)
- Crystal
- Domed, scratch-resistant sapphire crystal with anti-reflective treatment inside
- Dial
- Green
- Bracelet
- Steel
- Clasp
- Butterfly clasp
Movement
- Calibre
- Omega 8800
- Type
- Self winding
- Power reserve
- 55 hours
- Notes
- Listed by OMEGA as a Master Chronometer certified watch. Total product weight approximately 114 g.
What to check before you buy
- Tell the buyer the rating is 3 bar. Thirty metres is the lowest figure of any OMEGA documented here and it covers rain and hand washing only.
- Note that the calibre 8800 here is the same movement OMEGA fits to a 300-metre dive watch, which is a good illustration that the depth rating is a property of the case.
- Inspect the crystal's inner coating by looking through the glass at a shallow angle. OMEGA treats this one inside only, so haze behind the sapphire means a replacement.
- Check the 19 mm lug width before promising a strap change, and remember the clasp is a plain butterfly with no comfort adjustment listed.
- Judge the thin polished case under raking light. At 9.93 mm there is very little case flank and almost nowhere for handling marks to hide.
One movement, two very different watches
OMEGA specifies the calibre 8800 for this reference: self winding, 55 hours, Master Chronometer certified.
It specifies the same 8800 for the Seamaster Diver 300M, a watch rated to 30 bar.
This one is rated to 3 bar.
A factor of ten in depth, and the identical movement. That is worth understanding as a general principle rather than a curiosity: the water resistance is a property of the case, its gaskets, its crown and its back — not of the calibre inside.
Two practical consequences. A seller who reaches for "Master Chronometer, calibre 8800" as shorthand for a tough watch has said nothing about how much water it will survive. And a dealer who knows the movement is shared can be precise about what each reference actually offers, which is more persuasive than vagueness in either direction.
Thirty metres, stated plainly
3 bar (30 metres / 100 feet) is the lowest rating of any OMEGA documented on this site.
It means rain, and washing your hands. It does not mean a shower, washing up, or a swimming pool.
Nothing about the watch signals that limitation. It is a modern steel automatic on a steel bracelet with a sixty-year-old name on the dial, and buyers extend generous assumptions to watches that look like this one.
So write it in words, not as a number in a table: 30 m — keep it dry. One sentence in the listing prevents the most common complaint a dress watch generates.
Under ten millimetres, with nowhere to hide
The case is 9.93 mm thick on a 40 mm diameter, spanning 46.26 mm lug to lug, at 114 g.
Slim cases are unforgiving to grade. The band is shallow to begin with, and on a dress piece that narrow surface is usually mirror-finished, leaving nothing grained to disguise what lands on it.
Carry the watch into daylight, tilt it until a hard line reflects down the flank, and trace that reflection all the way around. You are looking as much for accumulated haze as for individual scratches: on a thin polished case, haze is what determines how the watch photographs and how it reads in the hand.
A buyer choosing a slim dress watch is buying its crispness. Say honestly how much of it is left.
Nineteen millimetres and a plain butterfly
Lug width is 19 mm — a real size, less commonly stocked than 20, and worth mentioning before a buyer goes strap shopping.
The clasp is listed simply as a butterfly clasp. Note what is not there: several other OMEGA references documented here specify a comfort setting, and this one does not. So there is no micro-adjustment to demonstrate and none to test; what there is instead is a hidden two-wing closure that nobody inspects.
Open it repeatedly. Both wings should release evenly and snap shut firmly.
The coating behind the glass
The crystal is domed, scratch-resistant sapphire with anti-reflective treatment inside.
Inside only. There is no outer layer to wear, which simplifies one half of the assessment — and no way to reach the inner one, which complicates the other. Hold the watch at a shallow angle under a lamp and look through the sapphire rather than at it. Bloom, patchiness or a milky sheen behind the glass is a crystal replacement, and it is close to invisible in photographs.
The dial is listed as green, the case and bracelet as steel.
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Sources
Not affiliated with OMEGA. Specifications are read from the manufacturer's own published documentation on the date shown and may change; the manufacturer's current documentation governs.