Short Answer
A fake Omega Seamaster Diver 300M 42mm copies the case shape, the wave dial, and the box. It does not copy the movement, the caseback, or the METAS Master Chronometer certification. The real watch runs a Co-Axial calibre 8800 under a sapphire caseback. Almost every replica hides a third-party movement behind solid steel. Counterfeit watches are illegal to import into the United States and illegal to sell. A buyer gets no warranty, no service from Omega, and no resale value.
Specs of the Genuine 42mm Diver 300M
- Case: 42 mm stainless steel, 300 m water resistance, helium escape valve at 10 o'clock.
- Dial: ceramic, laser-engraved waves, date window at 6 o'clock.
- Bezel: ceramic insert with a white enamel dive scale.
- Lume: blue emission on the hour markers, green emission on the minute hand and the bezel pip.
- Movement: calibre 8800, 55 hour power reserve, resistance to 15,000 gauss.
- Lug width 20 mm. Case thickness about 13.6 mm.
- Paperwork: METAS Master Chronometer certificate with a serial number Omega can verify.
Where Replicas Fail Inspection
Caseback and movement
The genuine watch has a sapphire caseback. You see a rotor with a wave edge, Geneva stripes, and blackened screws. Replicas ship solid casebacks, or glass over a rough automatic movement. A timegrapher reading on a fake shows low amplitude and a rate outside the METAS window of 0 to +5 seconds per day.
Bezel and dial
Genuine bezel markers sit in recessed enamel. They do not fade and they do not sit above the ceramic. Replicas use paint or a sticker. The wave pattern on a fake dial is stamped, so the ridges look shallow and the spacing drifts near the date window.
Lume color
Put the watch under a UV light. The real watch shows two colors: blue on the markers and hands, green on the minute hand and the pip. Most fakes glow one color, green, and the glow dies in under an hour.
Bracelet and clasp
The steel bracelet uses screw-in links and a clasp with a micro-adjust. Replicas use split pins and a stamped clasp. Weight differs by 15 to 25 grams on a kitchen scale.
Serial number
The serial is engraved on the caseback and logged with the movement. A replica serial returns no record. Omega can confirm a serial through a service center or an authorized dealer.
Legal and Practical Risk
18 U.S.C. § 2320 makes trafficking in counterfeit goods a federal crime. U.S. Customs and Border Protection seizes counterfeit watches at import and destroys them. The buyer loses the money. Domestic resale of a counterfeit watch is also a violation. Beyond the law, a fake rated at 300 m will not hold pressure at depth, the crown threads strip, and no watchmaker will source parts for it.
How to Check a Watch Before You Buy
- Ask for the Master Chronometer card and the serial number.
- Compare the serial on the card, the caseback, and the movement.
- Request a timegrapher photo with rate and amplitude.
- Check the lume under UV for two colors.
- Weigh the watch on a scale and compare to the published figure.
- Have Omega or an independent watchmaker open the caseback.