Cartier's Tank Must line launched in 2021. The catalog lists steel cases and yellow gold cases. A two-tone Tank Must, meaning a steel case with a gold bezel or a steel and gold bracelet, does not appear in that catalog. Listings that use the phrase point to a replica, or to a two-tone watch from another Tank line, such as the Tank Francaise. Confirm the reference number on the caseback first.

Genuine Tank Must specs

  • Small model: 29.5 mm by 22 mm. Large model: 33.7 mm by 25.5 mm.
  • Case thickness: about 6.6 mm.
  • Movement: quartz. SolarBeat versions use a photovoltaic movement with a rated service life near 16 years.
  • Crystal: sapphire.
  • Water resistance: 30 m, or 3 bar.
  • Dial: Roman numerals, "Cartier" printed at 7 o'clock, "Swiss Made" under 6 o'clock.
  • Crown: blue spinel cabochon, faceted.
  • Caseback: screw-down with four screws on quartz models.
  • Strap: leather with a steel ardillon or folding buckle.

Tells on a replica two-tone Tank Must

Plating color and wear

Replica two-tone cases carry a thin gold layer. The color drifts to orange, or to a pale yellow that reads green under store light. Wear shows at the lugs, the crown, and the caseback edge within months.

Crown cabochon

The genuine cabochon is a faceted blue spinel. Replicas use glass or resin. Look for bubbles inside, a flat cut, and a blue that trends purple.

Caseback and screws

Genuine quartz Tank Must cases close with four screws. Many replicas use a snap back, or six screws, or an engraving that sits shallow in the metal. Font weight on the engraving differs from the Cartier typeface.

Movement

A watchmaker can open the case in minutes. Genuine quartz movements carry Cartier markings and Swiss origin. Replica movements show no maker, or a Chinese quartz caliber. Some replicas use automatic movements. The Tank Must is not an automatic watch.

Dial printing and crystal

Pad printing on a genuine dial is sharp at 10x magnification. Replica numerals show fuzzy edges and thicker strokes. Genuine crystal is sapphire. Mineral glass scratches with a steel key.

Weight

Gold plating adds almost no mass. A two-tone watch that weighs the same as an all-steel Tank Must is plated, not solid.

Paperwork and service

Cartier ships the Tank Must with a box, a warranty card, and an international warranty. Cartier does not sell parts or movements to third parties. A quartz service at a US service center costs several hundred dollars. Prices on the brand site change, so check the current figure there.

Legal status in the US

  • 19 U.S.C. Section 1526 bars import of goods that carry a counterfeit mark. US Customs and Border Protection can seize and destroy a shipment.
  • 18 U.S.C. Section 2320 covers trafficking in counterfeit goods and carries criminal penalties.
  • Selling a counterfeit as genuine is trademark infringement. Cartier can pursue civil damages.

Checks before you buy

  1. Ask for the reference number on the caseback and compare it to the Cartier catalog.
  2. Ask for photos of the movement with the caseback removed.
  3. Have a watchmaker confirm the movement, the crystal, and the caseback screws.
  4. Cartier boutiques do not authenticate watches. Independent appraisers do.