The Omega Seamaster 300M "512 copy" is a replica of the 42 mm Seamaster Diver 300M. The number 512 does not appear in Omega's published reference lists for that model. Treat it as a seller or batch code.
What the 512 tag refers to
Omega reference numbers for the Seamaster Diver 300M follow the 210.30.42.20.xx.xxx pattern. No published reference ends in 512. Sellers use short codes to mark batches: bezel insert version, dial print revision, bracelet supplier, or movement swap. A code without a spec sheet tells you nothing. Ask the seller what changed versus the prior batch and get the answer in writing.
omega seamaster 300m 512 authorized dealer
Genuine baseline specs
- Case: steel, 42 mm wide, about 13.6 mm thick, 20 mm lug width.
- Bezel: ceramic insert, white enamel diving scale, scalloped edge, unidirectional.
- Dial: laser-cut wave pattern, date at 6 o'clock, applied indices with Super-LumiNova.
- Helium escape valve: conical, at 10 o'clock.
- Movement: Calibre 8800, Co-Axial escapement, Master Chronometer certified, 55 hour power reserve, 25,200 vph.
- Water resistance: 300 m, tested to ISO 6425.
- Crystal and caseback: sapphire on both sides, NAIAD lock caseback.
- Bracelet: steel, dive extension clasp.
What replicas get close
Case profile, dial wave texture, bezel color, and bracelet taper are the strong areas on current replicas. The 42 mm size matches, so the watch sits the same on the wrist. Sapphire and ceramic parts are common on higher batches.
What replicas miss
Bezel click feel, crown thread quality, date wheel font, lume color against the genuine, caseback engraving depth, and end-link fit at the lugs. The helium valve on a replica does not function. It is a cosmetic part, often glued or fitted with a dummy stem.
Omega Seamaster 300M 512 Buying Guide
Movement inside
Most replicas run an Asian 2824 clone at 28,800 vph, or a decorated movement with plates shaped like the 8800 at 25,200 vph. Decoration does not change the base caliber. Ask for a timegrapher photo showing rate, amplitude, and beat error. Power reserve measured by owners often falls below the figure a seller quotes.
Water resistance reality
No replica factory pressure-tests to 300 m. Gasket quality and caseback seals vary by batch, and a helium valve that does not seal adds a path for water. Do not swim or dive with a replica. A local watchmaker can pressure-test to 50 m or 100 m for a fee.
Checks before you pay
- Get photos of the crown side, caseback, clasp, and lugs.
- Confirm the movement type and beat rate.
- Request a timegrapher reading.
- Check bezel alignment at 12 and the lume pip centering.
- Confirm the return window in writing.
- Compare the price against other sellers listing the same batch.
Legal position
Counterfeit watches infringe trademarks. Import and sale are illegal in the US and the EU, and customs can seize a shipment. A replica is not a Swiss watch and carries no Omega warranty or service support.