The Cartier Tank Must 31mm is the smallest and most versatile take on a design that has stayed in production, in one form or another, for more than a century. This replica version copies the slim rectangular case, the brancards that flow into the lugs, and the crisp Roman numeral dial that make the Tank instantly readable across a room. Below is what to check before you buy.
What defines the 31mm Tank Must?
The 31mm case is the entry point of the Tank Must line, a size that wears like a dress watch on larger wrists and like a classic everyday piece on smaller ones. It keeps the same thin profile and squared-off corners as the larger 33mm and 41mm versions, only scaled down.
Key Features
- 31mm x 22mm rectangular stainless steel case with signature brancard lugs
- Sapphire crystal with anti-reflective coating
- Silvered or blue dial with black Roman numerals and blued-steel sword hands
- Automatic or Swiss quartz movement, depending on the version
- Quick-release leather strap or steel bracelet options
- 30m water resistance for daily wear
- Crown set with a blue synthetic spinel cabochon
- Screw-down caseback with engraved reference markings
The case is 316L stainless steel, polished on the sides and brushed on the caseback, and the crystal is flat sapphire on the better builds. Dial printing is either pad-printed or applied, so ask your seller which method the batch uses; applied numerals and a printed minute track are the closest match to the genuine dial. Strap choices run from alligator-grain leather to calf and steel mesh, and automatic versions use a 28,800 vph movement with roughly 38 to 42 hours of power reserve.
How close is the 31mm replica to the genuine?
The best replicas match the genuine case dimensions, dial layout, and hand shape closely, and the clearest tells are the weight of the crown and the crispness of the dial printing. Ask for macro photos of the dial, crown, and caseback before ordering.
Orders ship discreetly in plain packaging with tracking, and most US destinations see delivery in 5 to 10 business days after dispatch. Returns are accepted within 14 days of receipt when the watch is unworn and the protective films are intact, so contact support for a return authorization before sending anything back.
Is the 31mm size right for smaller wrists?
Yes. The Tank has always been a unisex design, and 31mm wears larger than the number suggests because the rectangular case stretches across the wrist. On a 6 to 7 inch wrist it reads as a classic dress watch rather than a tiny one.