Answer first
8240029 is not a Cartier reference number. Cartier watch codes begin with the letter W and hold 8 characters, for example WSTA0041. A 7-digit code with no letter does not match the Cartier format, so it comes from a seller catalog. The item behind it is a copy of a Cartier Tank. Cartier does not make, sell, or service the piece. Under US law the sale of counterfeit watches is a federal crime. Buyers get no warranty, no parts support, and no resale value.
What the Cartier Tank is
Louis Cartier designed the Tank in 1917. The case shape came from the Renault FT tank used in World War I: a rectangle with brancards on each side. Cartier sold the first Tank in 1919. The line today includes the Tank Must, Tank Louis Cartier, Tank Francaise, Tank Americaine, and Tank Cintree. Cartier is owned by Richemont.
Steel models carry the Tank Must name. The Tank Must Large measures 33.7 mm by 25.5 mm and runs on quartz. Tank Louis Cartier models use 18k gold cases and the hand-wound 1917 MC caliber.
What changes on a replica
- Case metal: 18k gold on the original, brass or plated steel on a copy.
- Movement: Cartier quartz or the 1917 MC hand-wound caliber, against generic quartz or a low-cost automatic.
- Dial print: Cartier uses set spacing. Copies show heavier text and uneven gaps at the XII.
- Cabochon: blue spinel on Cartier crowns. Copies use glass or dyed plastic.
- Caseback: engraving, reference code, serial number. A 7-digit code in place of a W-prefix code is the tell.
- Papers: Cartier ships a certificate, a numbered warranty card, and a box. Replica sellers ship generic packaging.
Legal status in the United States
Trademark counterfeiting sits under 18 U.S.C. 2320. A first offense carries up to 10 years in prison and a $2,000,000 fine for an individual. Cartier and Richemont can also sue under the Lanham Act for damages and legal fees.
US Customs and Border Protection can seize and destroy counterfeit watches at the border. The one-item exception for personal use in a traveler's baggage does not apply to shipments sent by mail. A seized package is not returned, and money paid to the seller is not recovered.
How to check a code
- Cartier watch references start with W: WSTA0041, WGTA0011, W4TA0008. A code with no letter is not a Cartier reference.
- Cartier keeps no public serial number database. Verification runs through a boutique or an authorized service center.
- Cartier service centers refuse counterfeit items. No repair, no parts, no battery change.