The best fake Omega 3604 for most buyers is the tier that machines the case to true vintage dimensions and runs a movement that copies the original caliber, not the cheapest listing that uses "3604" as a keyword. Three criteria decide it: whether the seller can explain what the number refers to, whether the case geometry matches the era, and whether the movement is a named caliber instead of a vague "automatic."

What "3604" means before you spend anything

Omega does not list 3604 in its current catalog. In the vintage market, four digit numbers in that range turn up as case reference stamps on 1950s and 1960s dress watches, and similar numbers appear in Omega's older caliber numbering. That ambiguity is the whole problem with the search term. A seller listing a fake Omega 3604 may be offering a replica of a slim gold plated dress watch, a replica of a Seamaster that carries that stamp on the caseback, or a watch with no relationship to the number at all.

Ask one question first: is 3604 the case reference or the movement? A seller who handles vintage Omega stock answers without hesitating. A seller who pasted the number into a title will not.

Option 1: Budget quartz copy

A quartz movement in a plated case, usually sold at the lowest price point in the search results.

  • Pros: lowest entry cost, accurate timekeeping, light on the wrist, easy to replace if it fails.
  • Cons: stepping seconds hand where the original ran a smooth sweep, plating that wears through at the lugs and crown, printed dials with wrong font weights, no resale value.

Buy it if: you want the look for one event and never plan to open the caseback.

Option 2: Mid tier automatic clone

A 316L steel case with a Japanese or Chinese automatic inside, usually a Miyota derivative or a clone of a common Swiss pattern, fitted with a sapphire crystal.

  • Pros: real mechanical feel, genuine 316L steel that resists pitting, serviceable by any independent watchmaker, decent dial printing at arm's length.
  • Cons: rotor noise on cheaper versions, extra case thickness from the movement spacer, date font and window shape that drift from the original, missing period details such as applied versus printed logos.

Buy it if: this is a daily wearer and you want a mechanical watch you are not afraid to scratch.

Option 3: High tier 1:1 build with a Swiss or Swiss clone movement

The top of the replica market, where the case profile, lug curve, and crystal are cut to match a documented reference rather than approximated.

  • Pros: correct case profile and lug curvature, sapphire with inner anti reflective coating, crisp dial printing, hand winding and hacking that feel like the caliber they copy, timekeeping within a few seconds a day once regulated.
  • Cons: highest cost of the three tiers, waits for stock, harder to service because parts are not sold openly, and it is still not a genuine watch.

Buy it if: you already own genuine pieces and want the closest visual match for occasional wear.

Five minute checks that separate the tiers

  1. Compare case diameter and lug width against the documented reference for that number.
  2. Check crown position, size, and how far the stem protrudes from the case.
  3. Read the dial printing: logo shape, the placement of the Swiss marking, and the weight of the numerals.
  4. Confirm the crystal material. Period dress watches used acrylic. Sapphire belongs only where the original had it.
  5. Ask for a photo of the movement with the caseback removed and identify the caliber before you pay.

Red flags in 3604 listings

  • The same photos appear across several listings with different case metals.
  • The movement is described only as "Swiss movement" or "high grade automatic."
  • Patina looks sprayed and uniform, or too orange. Real aging is uneven and follows the lume plots.
  • The Swiss marking is printed on a dial from an era where it did not apply, or absent where it should be.
  • Weight, thickness, and case material are given in vague terms with no measurements.

Legal and practical reality

Replica watches copy protected trademarks, and in the United States import of counterfeit goods is barred, with customs seizures occurring at the border. Domestic resale of a counterfeit carries its own exposure. That does not stop the market, but it does mean you should treat any purchase as final and uninsured, and never pay through a channel you cannot dispute.

Bottom line

Decide what 3604 means to you before you compare sellers. If you want a vintage dress look, the mid tier automatic is the sensible buy. If you want the closest copy of a documented case, pay for the 1:1 build and verify the movement photo first. If a listing will not tell you whether the number is a case reference or a caliber, the watch behind it is guesswork.