Short answer

Reference 322.10.42 is an Omega case code for a Seamaster Aqua Terra. The prefix alone does not name one watch. A complete Omega reference has 10 digits, and the last groups set the dial, bezel, and calibre. Fakes built on this case code exist in several grades. Three checks catch most of them: the movement beat rate, the depth and font of the caseback engraving, and the serial number match between case, certificate, and Omega records.

Read the reference number

Omega splits a 10-digit reference into groups. The first three digits name the case family. The next two name the material of case and bracelet, and 10 means stainless steel for both. The following two digits give the case diameter in millimeters. So 322.10.42 points to a steel Aqua Terra with a nominal 42 mm case, about 41.5 mm measured. The remaining groups cover dial color, hand style, and calibre. Ask the seller for all 10 digits. Type the full number into an Omega boutique check or a dealer spec sheet.

Case, crystal, and crown

Aqua Terra 150M cases in this code use stainless steel, a screw-down crown, and a water resistance rating of 150 m (15 bar). Display-back versions carry sapphire front and back. Fake cases copy the outline well. Differences show at the lugs. Real lugs have crisp bevels, a mirror polish on the flank, and brushed top surfaces. Fakes show soft edges and mixed finish lines. The crown logo on a real watch is laser-cut and centered. Fakes stamp the logo, and the teeth feel sharp.

Dial and hands

Most Aqua Terra references in this family use a teak dial: vertical lines on a sun-brushed base, applied metal indexes, and a framed date window at 3 o'clock. Real indexes sit flush and reflect light on one edge. Fake indexes sit high and show a glue line. Real hands have polished bevels and a flat fill of white Super-LumiNova. Fake lume pools at the edges. The date font matters. Omega date wheels use a narrow, tall font. Fakes use wider generic fonts.

Caseback and serial number

Real casebacks carry deep, sharp engraving: the seahorse medallion, Seamaster, Anti-magnetic, the reference number, and an 8-digit serial. Fakes engrave the same text with a shallow laser cut and rounded letters. Check the serial in three places: caseback, movement, and certificate. All three must match. Fake batches reuse one serial across many units, so a search on that number pulls up other watches. An Omega boutique or an authorized service center can check the serial against Omega records.

Movement

Co-axial Aqua Terra models use Omega calibres from the 8500 and 8900 families. These run at 25,200 vibrations per hour (3.5 Hz) and hold a 60-hour power reserve. Many fakes use a Miyota 9015 or a copy of the ETA 2824. Both run at 28,800 vph (4 Hz). A timegrapher reading of 28,800 vph on a watch sold as an 8500 is a strong sign of a fake. Real co-axial movements also show a free-sprung balance and a silicon balance spring. Fakes do not copy those parts.

Bracelet and clasp

Steel bracelets on most references have screwed links. Count the screws and check the threads. Fakes use pins shaped like screws, or screws that strip on the first turn. The clasp should close with one firm press. Real clasps carry a laser-etched Omega logo and an even stamp. Fake clasps show a rough stamp and a gap between the clasp halves when closed.

Verification

Three checks settle the question: a timegrapher reading, a serial check with Omega, and a caseback inspection under a 10x loupe. A watchmaker with an Omega parts account can open the case and confirm the calibre number stamped on the movement. Counterfeit watches carry no Omega warranty and no serviceable parts, and brand service centers do not service them. Genuine used examples of this reference sell in the low thousands of US dollars. A price far below that range is the first sign to walk away.