The Omega Speedmaster Reduced is a 39mm automatic chronograph. It is not a scaled-down Speedmaster Professional. It has a modular movement, 18mm lugs, and its own reference numbers. Copies are common because used genuine examples trade for about $2,000 to $4,500.
Short answer: measure the case and lug width, identify the movement, check the subdial positions, and read the caseback engraving. Those four checks catch most fakes.
Genuine reference numbers
- 3510.50.00: 39mm steel case, 18mm lugs, hesalite crystal, caliber 1140.
- 3539.50.00: 39mm steel case, 18mm lugs, sapphire crystal, caliber 3220.
Both run the same architecture. An ETA 2892-A2 base carries a Dubois-Depraz 2020 chronograph module on top. The stack adds height at the back, so the case stays near 12mm thick. Beat rate is 28,800 vph, or 4 Hz. Power reserve is about 42 hours.
Movement tells
A mechanical chronograph advances the center seconds hand in 8 steps per second. A quartz copy steps once per second. Start the chronograph and watch the sweep.
On the genuine watch the pushers have short travel and a light click. The reset snaps the hand back to zero in one motion. The winding feel is smooth, and the rotor turns with a low whir. On many copies the chronograph hand drifts after reset, or the pusher needs a hard press.
Case, crown, and pushers
Measure the case across the bezel without the crown. Genuine width is 39mm. Measure the gap between the lugs. Genuine lug width is 18mm, which is narrower than the 20mm of a Professional. Copies often use a 20mm case and a wider bracelet.
The crown on a Reduced is push-pull, not screw-down. Water resistance is low, around 30m. Pushers sit at 2 and 4 o'clock and stay close to the case flank. On fakes the pushers sit high, the crown is oversized, or the crown threads.
Dial and hands
The dial has three subdials, and they sit close to the center. Subdial spacing is the strongest visual tell. Most copies use an off-the-shelf chronograph movement, and the subdials land in the wrong spot relative to the printed track.
Check the printing under a loupe. Genuine text has clean edges with no bleed. Check the date aperture against the exact reference, because some Speedmaster models have a date and some do not. A date window on a reference that never had one is a mismatch.
Dials made before the mid-1990s use tritium, marked T SWISS MADE T. Tritium ages to cream or tan. Later dials use Super-LumiNova. A dial stamped T SWISS MADE T with bright white lume that glows hard is wrong.
Caseback and bracelet
The caseback carries an engraved Seahorse medallion, the reference number, and a serial. Genuine engraving is deep and even. Copies are laser-etched, shallow, and often show wrong letter shapes or a missing serial.
The bracelet has 18mm end links and a signed clasp with an Omega logo and a reference stamp on the inner blade. Check the end link fit at the lugs. A gap or a wobble points to a mismatched case.
Checklist before you buy
- Measure case width and lug width.
- Confirm the movement type and beat rate.
- Compare subdial position to a photo of the same reference.
- Read the caseback engraving and serial.
- Match the serial to the papers, then verify through an Omega service center.
Price is a signal. A 3510.50.00 listed under $1,200 with box and papers needs an inspection. A seller who refuses a check by an independent watchmaker is a risk.
One legal note for US buyers: selling a counterfeit watch as genuine is illegal. Buying or owning a replica is a separate matter, and the checks above apply either way.