A fake Omega Seamaster Diver 300M 42mm is a replica of Omega's 42mm dive watch, built to copy the case shape, ceramic dial, and bezel of the original. Prices run from about $70 for a quartz version to $450 or more for a high-grade automatic with a cloned 8800 movement. The 42mm figure is the case diameter, and it pairs with a 20mm lug width on both the real watch and its copies.
What does the 42mm size tell you?
The number 42 refers to the case width measured across the dial, not the lug-to-lug length. On this model the lug-to-lug span sits near 50mm and the case runs about 13.6mm thick. That bulk comes from the automatic movement and the 300m water resistance rating on the genuine watch.
Omega sells several Seamaster Diver 300M versions at this size, including steel, titanium, and two-tone builds. Replicas copy the steel model most often because it is the best seller.
Which parts matter most on a replica?
Case and bezel
Study the case profile first. Good replicas keep the lugs angled, the crown guards shaped right, and the helium escape valve sitting at 10 o'clock. The bezel should be ceramic with an enamel dive scale, and the grip should feel firm with no side play.
Dial and hands
The real dial uses zirconium oxide ceramic with laser-cut waves. Cheap fakes print the waves or use a flat texture that looks dull in daylight. Check the date window at 6 o'clock, the skeleton hands, and the lume color, which should read pale green or blue-white rather than yellow.
Movement
Three movement types show up in this model. Quartz is the cheapest and steps once per second. The 2813 and its clones are automatic but rough to wind. A cloned 8800 or a decorated 2824 runs at 25,200 to 28,800 beats per hour and sweeps much like the original.
Bracelet and clasp
Steel bracelets vary a lot. Low-tier versions rattle, use folded links, and come with stamped clasps. Better versions use solid links, screw pins, and a working diver's extension. Check that the end links sit flush against the case with no visible gap.
Water resistance
Never trust a replica to be waterproof. Factories may print 300m on the caseback, but gaskets and seals on copies are not tested to that level. Treat any fake Seamaster as splash-resistant at best unless a watchmaker pressure-tests it first.
Quality tiers: how they compare
- Tier 1 ($70 to $120): quartz movement, printed dial waves, folded bracelet, mineral glass or basic sapphire.
- Tier 2 ($150 to $250): automatic 2813, ceramic bezel insert, solid-link bracelet, alignment that can vary from piece to piece.
- Tier 3 ($280 to $450+): cloned 8800, ceramic dial with laser waves, sapphire with anti-reflective coating, tight tolerances on the bezel and date.
How to spot a low-grade fake
- Count the seconds hand. A smooth sweep of eight beats per second points to a 28,800 bph movement. One jerk per second means quartz.
- Tilt the dial toward a window. Engraved ceramic waves shift and catch light. Printed waves stay flat.
- Look at the date. Poor centering or a wrong font is a common giveaway.
- Weigh the watch in your hand. Steel cases feel heavier than plated brass or alloy.
- Read the caseback engraving. Crisp text with sharp edges is a good sign. Shallow, blurry text is not.
Common flaws in 42mm replicas
- Bezel markers that sit off-center or fade within a few months.
- Date wheels that sit high or low in the window.
- Crown threads that feel gritty and cross-thread when you screw them down.
- Lume that dies in 20 minutes instead of lasting through the night.
- End links that do not sit flush with the lugs.
- Hands that catch on the dial or on each other when you set the time.
Sizing and fit advice
The 42mm case wears larger than the number suggests because of the lug-to-lug span. A wrist under 6.5 inches may see the lugs overhang the edges. A rubber strap or a shorter bracelet cuts the visual bulk and keeps the watch centered.
Check the clasp position before you trim anything. Removing two links is normal for a 7-inch wrist, and a diver's extension adds length you may not need.
Are 42mm replicas worth the price?
A high-tier copy costs a small share of the real watch and reads close on the wrist from a normal distance. It will not match the movement finish, the magnetic resistance, or the resale value of the genuine piece. Buy for the look, not for the engineering.
FAQ
Is a fake Omega Seamaster Diver 300M 42mm waterproof?
No claim of 300m water resistance holds up on a replica. Seals are untested and casebacks may not seat right. Keep it away from swimming and showers unless a watchmaker tests it first.
Which movement is best in a replica Seamaster?
A cloned 8800 or a decorated 2824 gives the closest sweep and the best reliability. The 2813 works, but it feels rough when wound, and quartz is the least convincing option.
How much should a good 42mm replica cost?
Expect $280 to $450 for a top tier. Anything under $150 often shows shortcuts in the dial, bezel, or bracelet.
Can a jeweler tell it is fake?
Yes, if they open the caseback. Movement engravings, rotor decoration, and finishing differ from the real 8800. From across a table, a high-tier copy is hard to call out.
Does the 42mm size match the original?
Yes. The modern Seamaster Diver 300M uses a 42mm case with a 20mm lug width. Replicas copy those numbers, though thickness can differ by 0.5mm to 1mm.