The core rule for the replica Seamaster 300M market, including the batches sellers tag as 291, is to buy the build and not the listing. Photos of a genuine watch and a page of superlatives tell you nothing about who made the case, what movement sits inside, or how the bezel insert was produced. Before you send money, get four answers in writing: which factory produced the case and dial, which movement is installed with the exact caliber name, whether the bezel insert is ceramic or aluminum, and what the seller does if the watch arrives with a misaligned insert or a movement that stops. A seller who answers all four earns the premium. A seller who answers with "1:1 Swiss AAA" does not.

What the 291 Tag Means

291 is not an Omega reference number. Omega catalogs the Seamaster 300M under numeric reference codes, and the 291 you see in a title is seller shorthand for a batch, a factory run, or a storefront code. Two shops can use the same tag for two different watches, so the tag alone carries no quality guarantee. Ask which generation of the dive model the build copies, then compare the answer against the official spec sheet for that generation. The current 42 mm dive line, the wave dial variants, and the older flat dial versions all differ in dial texture, date placement, and bezel font. If a seller cannot name the generation, you are buying blind.

What to Verify Before Payment

• Case and dial source. Ask for the case diameter, thickness, lug width, and lug to lug measurement. A vague answer points to a generic case.
• Movement. Insist on the caliber name: an A2824, a PT5000, a decorated clone of the Omega 8800 or 8900, or a Sellita SW200 base. "Swiss movement" alone means nothing.
• Bezel insert. Ceramic with a lume pip at 12 is the target. Aluminum inserts scratch and look flat under light.
• Hands and date. Check the hand stack height, the sweep of the seconds hand, and the date font and window position.
• Bracelet and clasp. Look for a taper from 20 mm to 18 mm, screw pins, and a clasp with correct engraving depth.
• Water resistance. Ask whether the watch was pressure tested after assembly. Most replica dive watches are sealed to a fraction of the rating printed on the caseback.

Spec Bands by Tier

• Entry tier. 42 mm case, 14 to 15 mm thick, mineral glass or basic sapphire, DG2813 or A2824 movement, printed dial, soft insert. Expect a date wheel with the wrong font and a bezel that clicks past alignment.
• Mid tier. 42 mm case, 13.5 to 14.5 mm thick, sapphire with inner anti reflective coating, PT5000 or a clone 8800, ceramic insert with a lume pip, applied logo and indices. Most watches tagged 291 land in this band.
• Top tier. Case profile within half a millimeter of the genuine shape, Sellita or decorated ETA base, laser cut wave dial, correct date font and position, matching bracelet taper, and a documented pressure test.

Pitfalls That Cost Money

• A movement described as Swiss with no caliber name attached.
• A bezel insert that sits off center at 12, which is the single easiest flaw to spot in a photo.
• Lume that differs in color or brightness between the hands, the dial markers, and the pip.
• A helium escape valve that is cosmetic and does not seal, which turns a swim into a repair bill.
• Crown threads that feel gritty or cross thread on the first wind.
• Stock photos of a genuine watch instead of images of the actual unit.
• No stated policy for a watch that arrives dead or damaged.
• Seizure at customs with no refund path, which is a real cost in the United States.

FAQ

Is 291 a factory name?

No. It is a seller tag. Factories that build replica Seamaster 300M watches use their own internal codes, and resellers often invent new ones to make a batch look exclusive. Judge the watch on the specs you confirm, not on the code.

Which movement should I choose?

A PT5000 or a Sellita SW200 base gives smoother winding and easier service. A decorated clone of the Omega 8800 looks better through the caseback and offers a closer visual match. Avoid unbranded 21 jewel movements if you plan to wear the watch often.

Can a replica Seamaster 300M go in water?

Treat it as splash resistant unless a seller provides a pressure test result. Gaskets, caseback threads, and the crown tube on replica cases vary in quality, so showering or swimming carries risk even when the caseback prints 300 m.

How do I spot a low tier build from photos?

Look at the bezel alignment at 12, the date window position, the gap between the dial and the rehaut, and the shape of the crown guards. Those four areas separate a mid tier build from a cheap one before you ever see the movement.

Legal and Practical Note

Replica watches copy protected trademarks, and importing one into the United States can lead to seizure by customs with no refund. Factor that risk into the price you are willing to lose, keep the payment method reversible where possible, and confirm the return window in writing. A guide can help you avoid a bad build, but it cannot remove the legal exposure of the purchase itself.