The Omega De Ville Trésor 40 mm is a dress watch with a small seconds sub-dial at 6 o'clock. The "424" group is Omega's case code for the 40 mm Trésor. One common reference is 424.13.40.20.02.001: stainless steel case, opaline silver dial, leather strap, manual-wind Calibre 8511. A listing that calls itself a replica, a clone, or a 1:1 copy is not an Omega. Selling one in the United States is a federal crime.
What the number 424 identifies
Omega reference numbers are built in blocks. The first block names the collection and case family. "424" covers the De Ville Trésor 40 mm. The digit blocks after 424 code metal, diameter, movement family, and dial variant. Two watches can share the 424.13.40 prefix and still differ in dial color and strap. The full reference runs 14 digits, and the last groups decide what you are looking at.
Specs of the authentic 424.13.40.20.02.001
- Case: 40 mm stainless steel, three-part, polished and brushed
- Movement: Omega Calibre 8511, manual wind, Co-Axial escapement, about 60 hours of power reserve
- Dial: opaline silver, applied indices, small seconds at 6 o'clock
- Crystal: domed sapphire front, sapphire case back
- Water resistance: 30 m (3 bar) per Omega
- Strap: leather with a pin buckle or deployant clasp
Confirm each figure against Omega's own product page before you buy. Spec sheets get revised.
Why replica listings use this reference
Search demand for a luxury watch creates copycat listings. Those listings borrow the real numbers: 40 mm, Calibre 8511, sapphire, 60 hours. The numbers describe the genuine watch, not the item in the box. Copy movements are generic automatics or hand-winds with no Omega parts. Case metal is steel plate over brass or zinc alloy, which weighs less and pits with wear. Dial printing is stamped, not applied. A copy carries no Omega warranty and no service record.
Legal status in the United States
18 U.S.C. 2320 makes trafficking in counterfeit goods a criminal offense. The Lanham Act lets a trademark owner sue, and statutory damages for willful counterfeiting reach $2,000,000 for each counterfeit mark used on each type of goods. U.S. Customs and Border Protection can seize and destroy shipments at the border. Resale platforms remove listings on report.
Checks before buying a Trésor
- Ask for the full reference and a photo of the case back engraving.
- Match the movement serial through Omega's archive extract service.
- Weigh the watch. Solid precious metal and steel sit in a different range than plated base metal.
- Compare the asking price to current market data. A deep discount is a signal, not a bargain.
- Demand the original box, papers, and service receipts.
What this guide does not cover
It does not name sellers, quote prices for copies, or point to sources. No replica maker publishes verifiable serial data, so a copy cannot be authenticated, insured, or serviced by Omega. If you want the Trésor 40 mm, buy from an authorized dealer or a documented secondary source.