The top pick for a replica Omega Caliber 8605 watch is a build that runs on a decorated ETA 2836-2 clone, such as the Sea-Gull ST2100 or the Hangzhou 6300. Those movements keep a working day-date display, which is the function the genuine 8605 was built to deliver. The criteria that separate a good 8605 replica from a bad one are simple: does the calendar function match, is the base movement serviceable, and does the decoration hold up when you look at the rotor and bridges up close.
What the Genuine Caliber 8605 Actually Is
Omega Caliber 8605 is a self-winding Master Co-Axial movement. It carries METAS Master Chronometer certification, a free-sprung balance with a silicon balance spring, two barrels mounted in series, and magnetic resistance rated to 15,000 gauss. It also drives a day-date display. Omega used the 8605 in Seamaster Aqua Terra models, and the movement sits behind a sapphire caseback. That last detail drives the whole replica market, because a buyer searching for an 8605 replica is usually looking at a watch with an open caseback. The movement, not just the dial, has to look believable.
Top Pick: Decorated 2836-2 Clone
The best match is a 2836-2 based automatic with Omega style decoration. The 2836-2 family carries a day-date complication, so the function lines up with the genuine 8605.
- Pros: day-date works; parts and service come from most watchmakers; the base design is proven; a technician can regulate it.
- Cons: stock finishing looks nothing like Omega; sellers sometimes fit the wrong rotor engraving; a low-cost decoration job can look flat under a loupe.
Use case: pick this if you want the calendar to work and you plan to wear the watch, not just photograph it.
Option 2: Asian 2824-2 Clone
Many listings labeled 8605 use a 2824-2 clone with added plates and a display back. The 2824-2 has a date only.
- Pros: thin, accurate when regulated, simple to replace, decent power reserve.
- Cons: no day function, so the replica cannot match the genuine 8605 layout; sellers often hide the missing day wheel behind a dial with a printed day.
Use case: a reasonable choice if the model you want shows only a date window and the seller confirms the movement.
Option 3: Miyota 9015 Build
Some higher-end replica makers use a Miyota 9015 and add a rotor engraved to resemble Omega's.
- Pros: reliable, easy to source, good for daily wear, clean sweep.
- Cons: date only; the beat rate and gear train do not mirror the 8605; decorations sit on a Japanese layout that looks different from the genuine bridges.
Use case: best for buyers who value reliability over a visual match.
How to Vet a Seller's 8605 Claim
- Ask for a movement photo with the caseback off, not a stock image.
- Confirm the day and date both change and both are set from the crown.
- Check the rotor engraving. The genuine 8605 uses specific text and an arabesque finish, and the font should be crisp.
- Ask whether the watch takes an ETA 2836-2 or a 2824-2 replacement, and whether a local watchmaker will touch it.
- Judge the price in context. A decorated clone should not cost like a Swiss original.
Use-Case Recommendation
If your goal is the closest match to what the genuine Caliber 8605 does, choose the 2836-2 build and accept the decoration gap. If your goal is daily reliability, the Miyota 9015 is the safer pick. If the watch you want has no day window, the 2824-2 clone is fine. The mistake to avoid is paying a premium for a listing that names a movement it does not use. A replica labeled 8605 is a claim about looks and function, and only the movement photo can prove it.